"I haven't noticed any charging or performance issues with any VB batteries. I use them, and find they work just as well as any other brand.
The lower the voltage on your battery, the slower your rate of fire. So, a 9.6v battery will give you a higher rate of fire than this. The MAH is just it's capacity and how long it will last. For me, 1600 mah batteries when properly charged will last around 4-5 hours of decent shooting."