You cant go wrong with Sanyo. Recently, I bought some POWERhaus 2300 - but they only 2000. Sanyo Twicell garantee you at least 2100, and sometimes better.
Your batteires wil last longer and perform better, if you buy a charger with auto cut off. This is a pretty nice one, which also be usefull for a digicam and a lot of other stuff. http://www.thomas-distributing.com/lm-mscaa.htm