well since this was talked about with a 3.3 and tz I will just say I was much more satisfied with my 3.3. Had about the same power but when me and Bobbo raced in STL I seemed to have slightly more bottom end but on top end it wasnt lacking at all. I like the 3.3 because to me it has the same power, direct drop in, plus its only 135 dollars and seems to last a long time. That has been my experience between the 2 motors so please dont flame it. I didnt care for the O.S. that much