Either the 10 or the 9XL will give you the speed you want with stock gearing. The 12XL will perform even better, though ( less heating, ampdraw, more runtime and higher effeciency).
Will that 12xl on 6s be as fast as the stock nitro truck?
alot of guys are running 8xl's on 4s with the lst, will the 12xl on 6s be as fast as that?