Boston RX1, if you ride groomed trails you will be better off with the 1.25, for off trail and powder use a taller lug. a taller lug track needs more snow for lubrication of the slidders (hyfax). you will smoke your slidders using a 2" lug track on groomed trails (any hard packed surface). also you lose top end speed with tall lug track ( more rotating mass). a tall lug track used anywhere except deep snow (or water) will be subjected to premature wear.