These 3 products are identical cases all made by a company called Eix. In fact there are other companies renaming and selling this same case, so it should basically be a matter of price shopping for you if you choose this model.
Price is the strongest point for this case. I purchased the uNu Power DX-1700 on Amazon.com for $35. Near post-time for this story we found another clone of this case type selling for $29.99 on Amazon. Shop around.
There was one difference in the products we received: the RichardSolo case came with a screen protector.
There is no question that the case greatly extended the life of the phone. I'm in the habit of charging whenever and wherever I can, and since I got this case I haven't come close to running out of juice on my iPhone 4S. The went without charging it was about a day and a half of moderate to heavy use and I had about 30% left in the phone at the end of that.
The case itself feels bulky, but secure. Even with a conventional bumper on it my iPhone 4S feels fragile in my hand (and it's not uncommon for the glass on either side of the phone to shatter). Not so with the uNu. We didn't do any crash testing, but my phone felt much more solid in the case.
These cases have a power button and 4 indicator LEDs on the back showing the level of charge. Two people tested this phone with 3 different phones and, while we can't describe it precisely, there's something flaky about the case and the way it charges. At times, after many hours of charging, either the case or the phone or both would remain below 100%. We found that by charging the case and phone separately we didn't have any problems.
Like most of the cases here, the Eix/uNu/RichardSolo/Boost has openings for the various buttons, speakers, and headphone jack on the phone, and all of these are somewhat less accessible as a result. The speakers sounded just fine to me, but my hearing stinks. I tried several sets of headphones and all fit easily.
There's nothing stylish about this case. It's a utilitarian solution and the cheapest option in this group of cases. In terms of pure battery bang for the buck, the Eix/uNu/RichardSolo/Boost is the best bet.
Name: uNu Power DX-1700 External Battery Case for iPhone 4 4S Price: $59.95
Name: RichardSolo Power Case for Verizon/ATT iPhone 4/4S Price: $49.95
Name: Boost Case for iPhone 4 4S Price: $59.95
These products are all identical OEM versions of the same case. It's a high-performance case with available at the lowest price we could find.
- Good battery life
- Solid feel
- Charging is sometimes flaky