I have attained 3 HTC Incredibles from VZW and I had them send me 3 of the HiCap 2150 VZW batteries. They are a nice improvement if you are having battery issues and the size increase, to me, is not very noticeable. After a few days with it, you forget it is on there, and only after handling the standard battery equipped phone do you even notice the change in form factor.
When I first got my wifes incredible, the only battery I had on hand was the 2150 HiCap. So, we mounted it on there and she has not looked back, Have never mounted her standard cap battery, it is still in the original box. She has zero issues with the larger profile so she is sticking with it.
On my phone, I have no issue with charging mid day at the office, and since the big battery doesnt work with my Seidio Innocase, I choose to run the standard battery and my HiCap battery is still in the original box, untouched.
On my 3rd Incredible, the one I actually bought, in order to add a line when we switched my daughter over for her 17th birthday, we are still up in the air. I am concerned that my daughter will not manage her battery as well as she could, so I got her a hicap, but I also got her an Innocase. I am hoping she doesnt find a need for the extended battery so that she can use the case, but time will tell.
As far as the extra life from the HiCap, I have done no actual testing other than just seat of the pants. The HiCap seems to do about what one would expect, given the numbers. It definitely adds several hours to the phone under normal use. I could totally see it being the difference between making it all day without charging vs not. And the form factor is a non issue, to me. The only drawback is the lack of cases in my opinion.
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