I just got our 4 sx engines back together this weekend. All I can say is that I have never ridden anything that is as exciting to ride. We have always had Curtis Sparks built Honda Pro motors and they are impressive, but these Baldwin bikes are just mean. We ran the Honda against the KTM last night on the Black-Top. Just about 300 ft. and the 450 SX walked away from the Honda. It was real close to 40 ft. by the end of the run. I really believe that this season is going to be very interesting.