Pretty high capacity and somewhat long-lasting
343862
I've used this in my CX6400 printer for about the past three weeks now.  I've copied numerous papers and printed many internet pages.  So far, it's about 1/3 of the way through.  If there is something like it doesn't use the last 10% of its cartridge ink, I'll keep you posted.  Otherwise, if you got a printer that goes with this cartrige, you best buy it here because it has it for $5 cheaper than any other site aight.
3748356
The short summary:  these work great for bulk file storage in the home--built to be continually powered up and to store large amounts of data for the home user, power user, or small business.

I've got a love-hate relationship with WD:  their USB drives have been problematic and disappointing, but the Caviar Black internal drives have run very well for RAID 0 / RAID 5 gaming in my desktop PCs.  I bought these Red volumes to fill in the slots in a home server that had a RAID 1 array where a member had died...it turned out to be cheaper to buy three 4TB volumes, start over, and gain a ton more space than to try to dig up an exact match for the bad drive and still keep a smaller array.  This time around, I used Windows Storage Spaces, a feature in Windows 8 and above.  On Windows 10  64-bit I was able to set up a large storage space with Parity and use it for my system backups.

Western Digital have done a good job making it easier to understand all these drives, and if you stop by their site, you'll see what the color codes mean (like Green for everyday desktop, Purple for surveillance systems).  If you're big on the details with hard drives, you know that the way they're built makes some better for gaming, some for large files, some for continuous writes, etc.  The Red series is for storage:  the kind you stick in a file server and expect them to be running 24/7 or for long periods of time, and you're not needing super-fast response time.  They've been running continuously since I installed them and a periodic temperature check doesn't seem to indicate they're overheating and getting stressed.

So far I've been happy with the ease of use of the WD Red 4TB NAS desktop hard drives.  They were fairly cheap, they do the job, and I suspect they'll last me for quite a while in my home server.
1466615
For what it is, this small power bank does its job well.  However, in this day and age of larger and increasing battery capacity, the capacity of this power bank may fall a little short.

This power bank came packaged in a nice package should you wish to gift it.  Once I received it, I plugged it in to charge. It took about 45 minutes to top off the power bank from its partially charged state.

Once charged, I plugged it to my LG G2 that was at 15%. This charger brought the phone to 91% before dying.  With power loss transfer taken into account, the effective output is about 1900mah. This is in line with other power banks with 2500mah capacity.

The power bank is pretty compact, just a little larger than a fun sized candy bar. The red anodized aluminum is very attractive. One small complaint is that in this day and age, the relatively small capacity of this power bank may not be sufficient for higher capacity devices.

Disclaimer : I received this product at a discount in exchange for my honest and unbiased review. The opinions above are one hundred percent my own.
549286
I have a few different portable batteries for charging usb devices, but this is my favorite so far.  The capacity is fairly large for the actual size of the device when compared to many other 3rd party chargers.  It has a nice clean design, and the digital readout is great.  I have noticed that it may not be accurate down to the percent, but it is close enough in my opinion.

The LED light isn't very bright.  It's there if you need it, but I haven't had much use for it.

Overall, it does what it's supposed to do.  I did purchase this with a coupon discount.  Not sure if it is worth full price, but if you can pick it up on sale then it is a great value.
975818
I really like this hard drive. It's portable and hot-swappable, so I can use it on multiple machines in my house. I've always heard that external hard drives are unstable, but this one has not given me any problems yet (just make sure you turn it off before you unplug it from the system). I only have a few (slight) problems with this hard drive: 1) the separate power adapter can be a bit of a pain, expecially when you're nowhere near an extra outlet, and 2) the USB port is a bit wobbly. I'm always afraid I'm going to break it right off whenever I plug a cord in. You just have to learn to be delicate with it when the cord is plugged in, I guess. Those are the only problems I've encountered, though. Now I just need to figure out what I'm going to fill this thing up with.
388352
Got this because of the massive capacity and the fact it can output up to 19V. I can power all my 12V electronics from it.

Build quality is very high.

However.. the charger failed after six months or so.  The vendor did send me a replacement power supply at no cost, but I had to pay for onward shipping (I'm outside the US) and I was unable to use the powerbank for several months.
4592402
As far as I can tell, all portable usb batteries have roughly the same capacity per unit volume ratios, so the choice of device is determined by capacity needs and design appeal.  When I got this power bank, it was slightly bigger than I expected, but I love the design, it looks elegant and sturdy at the same time, feels very comfortable in the hand, and the flash-light is super-bright. Actually, it would be easy to make a mount and use it as a bicycle flashlight, for added versatility.  In terms of capacity, as I expected it charged my Galaxy Note 8.0 4600 mAh battery from near 0% to 100%, with a little power left (but not much).  I only used it a couple times, but so far, so good.  I think it's an ideal compromise between size and capacity for me. Definitely a good travel companion.
4840199
This battery has a huge capacity. Since almost everything uses USB today, this pretty much replaces having a big 12 volt car type battery pack. It isn't too big or heavy so I have it with me and can recharge cell phone, tablet, netbook and even laptop. It recharges one item at a time though. I tried using a USB hub but it wouldn't work.
2689921
Great device, it's expensive, good design and big capacity. Just remember where you keep it.
1493061
I've had this drive for over 2 years, using it to store media and backup files.  I carry it around a lot, and have dropped it more than a few times, but it's never missed a beat. It's nice and portable and has plenty of space for my needs. It comes with a double USB cable that plugs into two ports at once to draw extra power, but I have frequently left out the second plug and haven't noticed a performance difference.
4878119
I purchased mine about two months ago for carrying random files around. It gets banged and dropped with my keys every day, but it's held up well to rough use. There's even a white space on the back for labeling the drive. The space is a bit small, so I'm not sure what to put there. Maybe my phone number.

Cap is snug and won't come off until you yank it off. Eight gigabytes is plentiful storage for a USB drive of this era. The drive isn't ReadyBoost-capable, but at around $16-18 for 8GB, I wouldn't expect it to be that fast.

I've just ordered a second one to create a bootable drive for a couple of netbooks.
3501398
First off, allow me to say that I love travel drives. For me, they're the best invention to grace the computer world. I own about a dozen of different capacities and brands and I have no problem with any of them. Same is said for this one. The 8GB capacity on this is a great plus. My smallest drive is 128MB and I have yet to fill that one up, so this one will last a long while, too, I hope. I must admit that I'm biased toward travel drives such as this that don't need to have a cap removed with chance for losing it. Though, this flip over design is handy, it wouldn't be practical for those with arthritic hands. It is durable enough and works on both my XP and Vista computers.
4600714
Six months of continuous use and still going strong
3787329
I received this as a free review sample. I subtracted a star because while this is a decent battery, it is not best in its class. For one thing the 6600mAh capacity in a 6.1 ounce form factor is neither high capacity when 10000+mAh batteries are now common, nor light at over a third of a pound. Another reason why I subtracted the star is the ports max out at 2 Amps, whereas there are batteries out that go all the way to 2.4. Again, this is still a decent battery, but I did want to mention why I rated it the way that I did.

It is fairly fast, holding its own against wall chargers when I tested it with two Samsung devices (a Note 4 phone and a Tab Pro 12.2 tablet), and an iPhone 5s and iPad Air 2. Note that the two ports are marked Rapid. Do not confuse that with Qualcomm's Quick Charge because I tested my QC-compliant Note 4 and it did not flip into that mode.  Of course, there are no claims in the specs that this goes into QC mode, but the 'Rapid' labels may confuse some folks who own QC-compliant devices (and Go Puck does have a model that is QC compliant.)

This battery charges at a full 2 Amps, so if you have a 2 (or higher) Amp wall charger you can charge it from nearly empty to full in about 3.5 hours. Plus it does not get overly hot during charging or discharging, which indicates to me that it is well designed and constructed from quality parts.

Do note that all batteries made from this technology, including competing brands, are about 70% efficient. While this one will store a full 6600mAh, losses from heat and the transfer process, and the charging cable itself will reduce the usable capacity that you transfer to your phone or tablet to approximately 4620mAh. That is still a lot of backup - more than enough to keep my Tab Pro 12.2 tablet running four more hours over the eight hours I normally get from it, and double the time I get from my Note 4 phone (plus some!)

Bottom line: this is a high quality battery that performs well. It is designed to be wearable, which is not one of my requirements. It is a little on the large and heavy side for a 6600mAh battery, and at that capacity is lower than most business class batteries currently on the market. If you have special mounting needs this is probably your best bet. If you need a general purpose battery you may want to continue comparison shopping.
923597
Really great and compact, only wish I got a larger capacity.
4015434
Thanks to the helpful review of NLee the Battery God, I mean NLee the Engineer, I purchased this to HQRP battery replace my failing 500 series battery.  I admit the price stung a little but the battery works great and my Roomba goes longer than it ever did before seeking out the dock.  I'll try to remember to update this review with my experience with the battery longevity.  Unfortunately, most of these batteries don't last more than a year or two.  Let's hope the durability is extended along with its capacity.

Edit: 5/31 - Owned for about eight months now and it's still running strong!  I keep it on the dock charger 24/7 when not in use and run it 2x a week on average.

Edit: 5/2015 - I purchased this on June 2012 and it lasted until May 2015, so two years 11 months.  About as good as you can expect from a roomba battery and the price is reasonable.  I'll probably buy another.
4025137
Works well, looks good, only wish I'd have gotten a larger capacity after using for a few months now.