Firstly I'll just say that I bought the extended battery for the Revolution at a Verizon store a while ago (3000 mah; equivalent to the one for MetroPCS), and always found it very reliable. The EXTREMELY annoying thing was the back battery cover it came with. the phone looked deformed... to put it nicely. after about two months of having an annoying lump on the middle of my phone I was kinda fed up and so I started looking at deals online for diff. batteries. well I came across this thread and saw the 3900 AceSoft battery, but more importantly, the battery cover it came with.
So I decided to buy it... the battery itself was a bit larger than the 3000 mah one from Verizon/Metro so natrually I thought it would last longer. Yeah it does last longer than the stock 1500 but in comparison to the 3000 mah one from Verizon/Metro... it fails disappointingly.
Usually I use Netflix quite often via WiFi/4G. A 21 minute episode of a show would normally drain the battery anywhere from 5-10% with the 3000 mah battery. But with the Acesoft... I was getting more like 15-20% drainage. Surfing the web (on WiFi) with 3000 mah battery is great; 30 minutes and only 3% had dropped. With AceSoft, not quite the case. Noticeably greater amounts of battery were being used.
So basically, yeah... don't trust third party generic batteries. I'm not gonna lie though, the case the battery came with is MUCH better than the humpback whale of a case that came with the one from Verizon/Metro. So I will keep that, but definitely am going to ditch the disappointing "3900 mah" one and go back to the 3000 mah battery from Verizon/Metro. Funny how I basically just ended up paying $40 for a better battery cover...