I had one for a while. Makes a decent trackbike for the big RR tracks. I think the 450 Japanese bikes are just as quick if not quicker, but the 525smr has longer legs with a 6-speed and can still be geared higher. Big gap between 5th and 6th gear tho. Kinda falls on its face in 6th so only good for real long straights. Bullet proof motor and simple valve adjustments(no shims).