I have 3 2010's. have ran from 52 cross all the way to 70, laid back to sitting up, jr3 to superheavy, box stock to rwyb, karts are bad fast, mine are very predicable, a tad finiky/ sensitive , you do need a good tire program, +1 on the bite comment. Some people don't like them, I bought one and fell in love, and still learning more and more each time out. I have been off on tires on a low grip track, and still ran up front.....