i have a 8000 2-cell lipo i run in my MF2, i use it for practice, takes about 45-50 minutes to charge, and i can run it for about 20-30 min with a novak brushless. i pull it off just when i see a small drop in speed, i was told not to run it down all the way or it could damage the pack if you run it dead. i charge it with a duratrax ice charger,