I've had the whole gamut of sportiva's, (miuras being the best shoe EVER made) and these shoes do it all, just better for short durations. I sized them a whole size smaller then the Miura thinking i should go even smaller, but i sized them correctly! the flimsy lorica never turned crusty and always snapped back to original size. I have noticed that where the toe knuckle rubber doesn't cover is wearing thin, but it still has a tacky film in those spots!!! the rubber is thick and the rand is still intact after serious abuse for a season of sport climbing @ rumney(sharp rock) and bouldering @ pawtuckaway! $100 well spent and will definately replace when, if ever, they blow out!