The Thunder Power Batteries list the discharge rates:
http://www.thunderpower-batteries.co...batteries.html
The 6000 and 8000 mAh batteries discharge at 8-10C with 15C bursts. The 6000 mAh batteries are rated for 48-60A continous and 90A bursts. The 8000 mAh batteries are rated for 64-80A continous and 120 A bursts.
I personally wouldn't buy less than the 8000 mAh lipo.