I carry 3 spares ..you know just.in.case
The first battery I ever got I actually cared about - I would charge only when it's close to being dead and recharge it full wile the phone is off. Ever since I got couple spare batteries I stopped caring but I noticed the one I initially cared about gives me the best battery life. Correlation ? Must be one.. take care care of your batteries
I also believe Juggalo's C4rbon ROM boosted battery performance.