I've had my Andida for a few weeks now - absolutely spectacular battery. I ordered it from Amazon for $14 or something, came in the mail pretty quickly, and it fits in the phone perfectly. I did 3 or 4 full charge cycles and I've been getting great results. I could barely get 7-8 hours out of my original battery with very little usage. Minimal usage with the Andida can easily put it past 50/60+ hours. As of right now, I've got 73% left after 10 hours of light to medium use.
It's also important to note that overheating has never been an issue.