In past years i have never really known what a good loop frequency is for a drive train velocity controller. What is reasonable. I know this depends on factors like maximum sensor sampling rate and accurace etc. When do you start to reach the point of diminshing return?
I have never used anything other that the 40Hz (approx) that the radio data comes at. It is possible to do faster with the IFI RC but within limits - the Victors have a max limit of something like 20Hz (check this, I am going from memory).