it all depends on traction...on a high bite track the B5 in Buggy is amazing..... However on a really loose surface it needs to be tamed down..... it all depends on how much traction you have to work with.... The F11 like the B5 can be tuned with a tuned pipe.... a B5 2057 is very smooth, so is a F11 on a 2087........ But a B5 on a 2013 is a animal, and so is the F11 for that matter.......... The Modified B6 is very powerful, less explosive then the B5, but every bit as powerful and fast !