It's been a couple days, I already broke in the battery and after many tests, I am impressed =]
At first I wasn't getting the results I expected but after a couple of recharge cycles and battery stat wipes, It's giving me what I paid for.
Being slim batteries of course you're not going to get insane battery life, but they definitely get you through the day without needing an outlet.
I'm a heavy user, I use Whatsapp, Live Profile, Go messenger for facebook, occasional skyping, twitter and of course texting. I make about 5 calls a day and work in a building with poor service. Check my facebook and news every now and then and open pandora for my daily commute. My phone never gives me less than 12 hours everyday. Not to mention I use my phone as a hotspot at home and sometimes at work.
So if you're looking for good quality batteries just to get you through your daily hustle and don't want to add bulk, and don't want to have to be switching batteries everyday (like the ankers!), this is most def the battery to get. It's worth the bucks.
-Galaxy S3 T999 w/Infamous 4.7.5
-HTC One S w/ViperOne S 2.1.0