from experience....the 600 class the top dog is the 636, that bike feels so pissed off that you have to twist.....the cbr has no guts, the gsxr has no balls and the r6 is not vary comfortable.....you can be running a hundred in 3rd and slam the 636 into 1st and it WILL NOT LOCK UP THE BACK TIRE....the tranny in the 636 and 6r are amazing...i've ridden every 600 hard as i possible can...but the easiest bike to stunt is by far the 600rr and R6...my .02's