I'm new to Electric. I'm currently using a Power10 in my Katana MD, w/2100, 3C, 11.1v batteries. I only get 8-9 minutes duration, but battery size is a limiting factor since the Katana has a small battery compartment. Can I use something else, like a 7.4V 3000Mah without degrading motor performance??? And what is most important when choosing a battery, Mah, V???????