I put mine on this past saturday and I love it so far it seemed to open up my mid and top considerably. Just looking to see everyone else thought of how theirs have performed. If you havn't tried one I highly recommend it especially if you have anykind of head work.

P.S. All I do with my YFZ is drag race not sure this carb is good for MX or trail riding I believe it is mainly a drag carb.