Not good for larger hands & requires excessive force to click the mouse
922469
This mouse looks nice and calls out some nice looking specs but I did not like the feel of it. It felt like it took too much effort to click it and the mouse felt short and stubby. I tried giving this away but once people tested it out they didn't like it either... maybe it only fits some people hands. Since purchasing this I have purchased a Logitech mouse and it is great, if you have medium to large hands I would not recommend this mouse.
2032544
I just bought this mouse and wanted to get rid of it right away.
Drawbacks:
1. The Switch Application button (the one on top) is located way back. I always have to curl my finger hard to press this button.
2. The palm rest is two high and it feels like you do not rest your palm at all. Sometime, it hurts your ankle
3. The Back button is designed way back. I do have to pull my hand back to be able to press this button => extremely inconvenient
4. The Forward button is located on the right, I rarely use it since it hurts my little finger everything I tried to locate and push it
5. The software does not work instantly. Sometime, it takes a few seconds to close the application compared with instantly by selecting Close application button on the application window.
6. If you use mouse a lot while surfing internet, I do not recommend this mouse. You are not able to combine relaxing your palm on this mouse and using all 6 buttons at the same time.
1999731
This is TOO small for my big hands. The edges of the control wheel that controls all the activities are about an eighth of an inch away from the edge of the shuffle - making it as difficult to handle as a needle and thread. I do admire the compactness but this gets no stars for ergonomics. The fingers you use to hold it (thumb and forefinger) are also the only ones that can control it - which means you have to use two hands (two fingers to hold it and two fingers to press the wheel. I preferred the previous shuffle because it was longer in the body and you could hold and manipulate it at the same time with one hand.
2155148
When I turn the computer on I have to intiate the mouse, push and hold the button on the USB Connector. Then I have to turn the mouse over and do the same (You need a sharp object since the button is small and recessed). This also has to be done when the computer goes to sleep. It is much easier to use the touch pad. I am returning the item, even though I will have to pay shipping.
183506
The ring finger rest is just a rest, not a button. Therefore you lose mouse shift functionality which would otherwise effectively double the amount of keys available to the thumb. Instead, there is a red button awkwardly placed next to the pointer finger, but you have to pull your pointer finger off of left-click in order to use it. Additionally, the mouse wheel only scrolls up and down, and clicks. There is no mouse-wheel-left. No mouse-wheel-right. Finally, the texture of the mouse is unnecessarily grainy and grippy. I guess this is to improve your grip. But with an MMO mouse, this is completely unnecessary and just makes it uncomfortable to touch. If you want a good MMO mouse, I would suggest the Logitech G600.
4555348
It definitely takes some getting used to, but my wrist is happy so I guess that's all that matters.  Another note that might be helpful:  I am a tall female, so my fingers are long but it seems to be fine.  My husband and my tall teenage boy do not like it.  Their hand (pinky side) tends to drag on the desk.  I think the problem for them is more that their hands are wide, not that their fingers are long.  The mouse is at MY computer, anyway, so it is fine if they don't like it  ;-)
4858309
Small size mouse than what I am use to so it was uncomfortable to use. I also have my left-right click fingers spread apart but with the small size and extra mouse buttons on the edge of the clickers, I had to keep my fingers closer together which was also uncomfortable.

Depending on your hand size, you may want to consider it before buying.
4821351
Bought as an opened package.  Now I, probably, know why it was (opened and returned).

Pros -
1 - Nice feel and design for larger than average sized hands.
2 - Able to finely control mouse pointer on screen.
3 - Quick, easy, and trouble free installation.
4 - Scrolls through pages quickly.
5 - Able to turn mouse on/off with slide switch on the bottom.

Cons -
1 - Scroll wheel way too sensitive.  Once a spot is reached on a page it doesn't stay on the spot chosen, i.e. page continues to "drift" after you stop scrolling.
2 - Because of wheel sensitivity, editing/keyboard operations become downright annoying and difficult.  The mouse pointer does not stay where you put it in the first place - it tends to continue moving.

Conclusion: Buy this mouse if you ONLY want to play games or JUST scroll through the Internet (surf web pages).  Once you take your hand off the mouse/scroll wheel the pointer/page will, generally, not stay put.  This became so annoying, I removed the mouse from my system.  Too bad, I liked its fit to my hand...
2494305
you can't rest whole hand on mouse . At the same time you need lift your wrist vertically to rest on thump rest. Wrist support mouse pad also no help.
1918293
The sloping side of the mouse makes it very difficult to pick the mouse up off of the table surface.  Buttons were positioned okay, however could not pick the mouse up to move it (without moving the cursor on the screen)  I bought it for the thumb button, but ended up going back to my old mouse that does not have a thumb button, just too difficult to use on a crowding desktop.
3229760
This is such a cool mouse, but I'm still not going to use it.

I won't go over how its designed--you can read other reviews.  But its almost magical.  Also a great on/off switch.  And the nano sized transceiver is great, I wish Microsoft would copy it for all of their other mice.

All of that said, its a big pain to use.  The arch is too small, for my hands anyway, so you end up having to hold you hand in the air a bit, certainly the rear part of your hand, and can only really rest your finger tips on the front of the mouse.  The buttons are VERY stiff.  And since you're not able to rest your hand on the mouse its a bit hard to push them too, since doing so would tend to move the mouse backwards.  If you have small strong hands, it could be neither of these issues will be a problem for you.

Since the surface of the mouse is mostly elevated off the surface, it tracks marvelously, even over a tablecloth which would cause a regular mouse problems as it bunches up or whatever.  Simply not an issue here.

There is no back button, which is a big loss for me.

The touch section works VERY well as far as I'm concerned, including the fast 'spin' of the wheel if you move your finger quickly.  The simulated wheel clicks, presumably created with a little speaker someplace, are also very magical and cool.  That part works really well.  However, with no middle click the normal paste function in Linux is gone also which is a giant pain.  Won't bother you much if you're a Windows user though.

If it were up to me, Microsoft would redesign this to make it larger or at least offer a large version of it.  They'd also do something about how stiff the buttons are.  Then I'd try it again.  For now, its getting packed away to at most be used on trips.
968393
It looks big but surprisingly doesn't provide enough support for my whole hand, I keep finding my palm and fingers keep hanging just off the side of the mouse which isn't very comfortable. I also found that the material the mouse is made of is way too smooth, it's difficult to get a good consistent grip as my hand keeps sliding off. Also, the side buttons don't appear to be functioning for me, they aren't going back or forward
4781894
The size and feel of this mouse are really good. The problem with this mouse is the click wheel. The wheel is really loose and moves too easily. It's fine for scrolling, but when you try to middle click a link the wheel moves a bit and scrolls off the link. If like me you like to middle click a lot to open pages in separate tabs, this mouse is effectively useless.
1047479
I have large hands, and if i don't claw grip it I can't easily use any of the buttons. It gets the job done but makes your hand ache if you keep a claw grip on it for too long.
4470016
Maybe this mouse just isn't for me, but this "ergonomic" mouse seems to put more strain on my fingers/wrist than my standard Anker mouse.
67374
This mouse lasted all of 5 minutes for me.  The buttons felt awkward, and sometimes even painful to use. Set up was easy, as was button programming, but it just hurt my hand too much to be used consistently. If you've got bigger hands, or don't have issues with the button placement, this may work for you. Unfortunately, it's lack of use comfort meant it got returned.
1358411
the mouse is too big for a woman with regular hand size. due to the size, clicking needs a lot of pressure than a regular mouse. also, makes my thumb hurt. i do not recommend this mouse to ppl with small hand