Interesting ive had 3 pairs of Xtalon 212s..The first 2 pairs the uppers went very quickly and the grip, But my 3rd pair lasted over a year and i find that when coming down a steep grassy slope if i heel strike coming down they grip as well as the 272s..In comparison to the 272 Mudclaws Ive had for nearly a year and the grips going unfortunately they seem very wide in the forefoot and im reluctant to buy another pair so i suspect my next shoes will be back to the Xtalons which are comfier and tighter fitting more like walsh.