Great mouse with a major issue
922282
I like this mouse and the bluetrack technology is great and it fits my hand well but after using it for a few monthgs the left click started squeaking. I don't know if this hapopens to everyone but it's terrible especially while playing games and shppting a semi autoamatic gun it squeaks and squeaks but everything else about the mouse is great
81481
I've been using this gamepad for World of Warcraft for quite a few months now and I can say that I absolutely love it. There are already plenty of other reviews that go into detail about it's characteristics and such but I thought I should take the time to mention one major problem the device has. Periodically, the LCD Manager will freeze and begin to take up as much as 50% of my CPU, requiring me to force quit the application in the Activity Monitor and restart it. This problem is documented in forum posts on Logitech's official website and as far as I can tell, the problem has existed since before the latest software update, which was in August, 2010! If Logitech can get their stuff together and make a profiler and LCD Manager that is on-par with it's windows equivalent (which is phenomenal), this will be a 5 star product for Mac users.
2497745
I can't, in good conscience, give this more stars because the mouse does appear to have a manufacturing flaw of some sorts. Like many other reviews have stated, my mouse recently began disconnecting if it is moved in a manner that it does not like and I have no idea what that manner is because it just happens whenever it wants. I can't even pick the mouse up to clean it because this almost always causes it to disconnect even though the cord is barely moved. It's also disconnected without me lifting the mouse.  I'm also wondering if the right button is having some kind of issue on occasion because the cursor will disappear sometimes while I'm playing a fullscreen game, which is what is supposed to happen when I press that button and move my character, but the cursor is supposed to reappear once the button is released and sometimes it does not reappear.

[Edit] I forgot to mention that one night when this mouse disconnected, in the middle of trying to play an MMORPG, it wouldn't reconnect until I rebooted my computer. Ever since then, I keep another mouse plugged in in case of emergency.

[Edit 2] The mouse stopped working while I was writing the return request and now it won't work at all. I've unplugged and plugged it back in several times and I've rebooted the computer twice. Now all I get is the pop-up saying "USB device not recognized".

I guess I need to see about getting a refund and then look for yet another mouse.

I really liked this mouse until the issues cropped up as it seemed to work quite well and it is quite comfortable to use. I have an old cloth-top mouse pad that I use with this mouse and the mouse works quite well on it.
893522
I'm between 4 and 5 stars with this mouse.  Overall I'm happy with the purchase, but only because I got it for a good price with a Gold Box deal. I wouldn't pay more than $50 for this mouse.  It's heavy and balanced, which is nice. My hands are large, so it's not a perfect fit for me.  I like the wireless nature of it, and the look/functionality is great.  The feel is not perfect though, so I'm only giving 4 stars.

UPDATE as of 12-19-12

After about 6 months of use, this mouse has failed. It has succumbed to the sticking-button issue (when clicking and holding, for selection in CAD).  This makes the mouse unusable. And there's nothing I can do about it...

UPDATE as of 12-2-16

The mouse started working again, probably a year or more ago.  The double-click issue has gone away.  Also, after trying to latest Logitech mouse, I realize that this is actually the best mouse to own.  I've purchased several others in the last few months for co-workers and for other uses.
1590613
It's a great mouse when it works. Unfortunately it has a design flaw where the free spinning mouse wheel mode will stop working (in one direction or both directions). I received a unit where this flaw was present from day one. When I called Logitech, they said they could not help me with a refurbished unit. If you could rely on this model long term, a refurb unit would be fine, but you can't. I suggest that you buy another model or buy this model new. It's a great mouse, but 90 days isn't enough time to save it from itself.
2642096
I've been using the Naga Epic as my primary mouse for the past 4 months. The mouse is excellent in use and is fantastic for anyone that enjoys MMOs. There is a learning curve with the placement of the buttons on the side grid, but before long you won't even remember having a hard time finding the right button to hit. I cannot imagine going back to playing MMOs and activating skills with the keyboard, the experience with the Naga Epic is that good.

Unfortunately the Naga Epic has serious technical issues that prevent it from being a good user experience overall. The mouse offers the option of using it in either wired or wireless mode, which you can switch between on the fly by toggling a switch on the bottom of the mouse and switching the USB cable from the wireless transmitter/dock to the mouse itself. The main issues with this mouse are somehow related to this ability, as the mouse frequently becomes unresponsive and will not "wake up" until I switch the connectivity mode (i.e. if I am wired, I must go wireless; if wireless, I must go wired). At first I thought this was a battery issue and I was not properly charging the mouse, but this unresponsiveness issue still occurs when the mouse is being used in wired mode and is directly plugged into a power source; it simply will not become responsive unless I switch to wireless mode. This can be very frustrating to have happen mid-game. In my experience, this issue happens multiple times per day, and has continued to occur even after updating the mouse to the current firmware version.

That said, I still really enjoy the ergonomics of this mouse and the button grid is excellent for use in MMOs. My only wish is that I had bought the standard, wired version of the mouse. I would have saved money and likely had less connectivity issues.
2968655
I had an MX518 for a few years. Best mouse I had in a long time. Then when that one stopped working, I saw that they had an upgraded version of the MX518, just a new name for it. I was quite impressed with the new mouse, until about a week ago. The intermittent disconnects are absolutely driving me nuts. I cannot play an online game (COD:Black ops 2 mostly) constant disconnects for a few seconds at a time. Always happens as I'm in a gun battle. MX518 was a great mouse, never had this problem. Seems a lot of people are having the same problem with this mouse. I have now ordered the G500 and fingers crossed. I cannot knock logitech because most of my hardware is logitech and I have always had great luck with their products, aside from this POS mouse. I decided to go with the G500 because it is a laser instead of optical so it seems people say if you are a gamer lasers are more responsive. I didn't buy the new mouse from amazon, but I will still add onto this review to give you a good idea if its worth it or not.
3215703
Let me start by saying that I love the feel of this mouse and keyboard combo. Really my favorite design I've tried out recently to the point where I bought one for work, one for home, and another as a gift. However at this time, I have to give this a negative review and a recommendation that you do not purchase. The USB dongles are extremely fragile on these devices. I had mine break while was sitting in my laptop bag in an otherwise empty pocket. I am not rough on my electronics.
Here is the real problem- Microsoft does just about nothing to support these devices. If the USB dongle breaks, they DO NOT sell replacement ones. If you buy other brands like Logitech, they have models that can be reassigned to a different dongle if yours is lost or broken. Support was useless when I called for help as they are with most lower price hardware issues (expected).
Until they offer some way of addressing this issue, I highly recommend you either stay away or plan on paying full price for a replacement if there are any issues (which conveniently seem to happen outside of the 30 days...
If you do get one, you'll probably love it like I did until it breaks and becomes a very expensive set of bricks.
1352444
I've purchased two because of a broken MB1 (left click), would double click whenever held down (full auto in a FPS would stop sporadically, highlighting things).  Same issue happened w/in 6 months of purchasing both.  I tend to pick the mouse up and put it back down a lot due to a small mouse pad.  I want to say that's why I've had this issue; so if you pick your mouse up while playing, maybe check out some other options.
632371
I'm working under Windows 7, so my mouse works just fine. Got the drivers from their website and didn't have any hassle setting it up.

The mouse itself feels amazing and I got used to it in only a few days. My had feels extremely comfortable with it. The buttons are placed in good locations and have nice response.

The ONE drawback that I REALLY dislike is that they're using Razer's Deathadder's mousewheel, and just like my deathadder that I have since discarded, this wheel stops losing its precision after a few months of use. The mouse will jerk in the opposite direction from where you scroll it, mostly because the wheel is made out a squishy plastic and the divots for each stop position are extremely small.

EDIT: An example is here: [...] it seems like this can be solved with lubricant or simply blowing on the mouse. Because this is solved, the mouse is great!

I'm very displeased with this decision by Func, as the rest of the mouse is a great piece of engineering and ergonomics.
505608
This is my 3rd Logitech Wireless Anywhere Mouse MX, which I purchased on 10/13/2013. The previous one I bought was about a year before that. With all three, after about a year, the mouse started to act up. This one is now periodically double clicking when I just click once on the left mouse button. The mouse has been fantastic up until this problem started to occur. I liked the mouse so much that I kept replacing it with the exact same one, hoping that it was just a fluke, but clearly it's not. I'm not going to buy a 4th one.
2942893
Hello. This has been the absolute best mouse I have ever owned. However since buying it I have had 1 issue with the left click and 1 issue with the thumb click. If you google g9x 'infamous double left click' you will see the issue. It required me to open up the mouse and bend the tiny metal piece and then it continued to work just like new. The left thumb button may have the same issue but I think it is more complex to fix on my own. I am hoping that the manufacturer will see this and respond. I am filing a claim right now on their website and will update the status here. I have high hopes because I've enjoyed so many of their products in the past.
3039786
I've been using Steelseries for a long time, starting with my passion for Counter Strike. I'd always found their products to be extremely well built, and usually one of the top performers in its category. This mouse is no different. It feel great in your hand, has a great weight to it, and performs wirelessly as well as any wired mouse I've used in the past. It has some great features etc etc, but the reason I'm writing this review is my distaste in one glaringly large oversight.

The cable. There is a Micro USB connector that connects either to the base, or to the mouse, allowing you to transition from wireless or wired. This also allows you to charge the mouse while using it. That's all great, and I love the idea, but the size of the port is proprietary. This means that all those USB Micro cables you have lying around won't fit. As you can see in the attached pictures, there are grooves cut out in the sides of the connector that made a regular port unable to fit, even if its near the same size. That's a huge annoyance, but the design in use allows the clip to lock in, offering some stability when using it in wired mode. I figured it's a worthy sacrifice at first.

I have a desktop and a laptop, and this mouse is great enough that I'd prefer to bring it with me rather than just leave it with my desktop, or leave it in my laptop bag. I figured the modularity of the mouse made it a perfect candidate, however the aforementioned problem stops this idea in its tracks, and here's why.

You cannot buy just the wire. I repeat, you cannot buy just the wire. I contacted support baffled by the idea of being unable to purchase the wire, as it'd clearly be preferable to RMAing the entire unit upon damages, and they confirm that it would be impossible to acquire just the wire.

> We have over 400 products in our portfolio and cannot feasibly provide parts for all of them. We provide what we can but these parts are not on the list of what we provide I'm afraid.

I'm shocked, and honestly confused as to why it is difficult to provide a USB wire. If the wire is going to be difficult to provide, then perhaps going the proprietary route was not the best option during the design stages.

I wouldn't recommend buying a car that requires a visit to the factory to change the battery, and I won't recommend a mouse that requires an RMA to replace a universal standard wire. Unfortunately, the support problems loom over an otherwise great mouse.
2206914
I love this mouse when it works. I have bought it twice now, the first one lasted about a year, the second, about a month (to the day, and of course that day was after the window to return it closed).

The first one stopped working and it seemed to be related to the mouse itself. I replaced the batteries, no luck. I unplugged, turned off, restarted, no luck. I bought the new one. The USB port stopped working, and it is just out. No more dice at all. I am super sad because like I have said, I love this mouse. I just really need to it work.
183635
I love the feel of this mouse and it's tracking.  There has only been one issue so far.  That issue is that once or twice a day, the mouse disconnects.  The DPI light flashes red for a moment and then the mouse is unresponsive.  It will not reconnect even if I push the connect button on the bottom nor if I remove and replace with the battery.  I have also tried removing it from my known devices list and then re-adding it back.  Unfortunately, once it goes into this mode, it will not show up as an available device so that I can add it back.  There are no instruction on how to reset the mouse.  I have tried holding down the connection button for 30 second (but that did not work).  If I can get this connection resolved then I will increase my rating.
1185715
I bought this in March 2011 and at first I was in love.  The button layout, feel, size, and highly customizable drivers are all great.  Tracking is excellent also.  However...

A few weeks after purchase I started having problems with erratic tracking on my Steelseries cloth pad.  There was no visible debris in the lens area but swiping the area with a cotton swab would fix it for a few days.  This continued until I bought a different brand of cloth pad.  I never had that problem with previous Logitech mice, even my G9x which is supposed to have the same optics as the Kone.

Around that same time I started having problems with erratic scroll wheel behavior.  Constant scrolling down would sometimes not respond or even scroll up (and visa versa for scrolling up).  You can find videos demonstrating this on Youtube.  Anyway, someone suggested a small squirt of WD40 next to the wheel which completely fixed it for a month or two.  Today the scroll wheel stopped working altogether.

It's a shame because when it worked the mouse was as close to perfect as I have ever had.  On the other hand it is the first mouse hardware failure of any kind I have had in nearly 20 years.  I'd chalk it up to bad luck except for all the posts about similar problems in forums.  Hopefully they will fix these issues in a future version.
4537208
I have owned the G602 for a couple years now and a serious problem has popped up within the last couple months.  It has started to think that, when I single click a link, that I'm double clicking.  This is making not only gaming but just the meare use of the mouse very annoying.  From looking at Logitech's forums, this is a common occurance with many of their mice.
I left an email with their support complaining about this, but I have no idea if they will get back to me.  I shouldn't have to buy a new mouse ever year or two because of poor quality.  If I have to, I will buy a mouse from a different manufacturer.  Maybe I'll get what I pay for.