Check out mountain preformance web site, don't forget to add anti ratchet drivers and MPI's tranfer kit while you are switching out. If I was starting from scratch I would go 156-159",3" pitch and MPI's lightweight skid. I love what I have, but instead of spending a $1,000 with hartman, I would spend $2,000 with MPI if I was starting over. The extra track is great, does not have any negative effect on handing. You might want to up your hp a little to take better advantage of extra track. I got rid of my RX1, switched to mtn viper. I'm having ball on the viper. Starting Line Products has triple pipes and canister that adds about 22 hp ish to a mtn max, drops about 11 lbs ish, for $700 ish. Check out their web site and order a free cataloge.