Thinking about going to semi-slicks, at least on one tire for now. I was thinking about putting one Maxxis semi-slick 2.35" in the rear, since I don't need as much cornering traction there. Also thinking about putting a fatter tire in the front, maybe a 2.5", but I want it to roll as fast as possible. Anybody know which type is the fastest yet has lots of traction? Would this setup work for "aggressive XC", sometimes 12 mile XC races?