Oakley sport glasses are quite overpriced but the lenses meet ANSI Z78.1 standard for impact resistance. Once, I was riding head down (yes, careless) and crashed (at low speed) into a work truck parked in the bike lane with barely visible hazard lights and no trailing safety cones. My right lens hit the ball hitch mount and the only damage to the lens was a chip in the Prizm coating. Yes, I recognize that this is only an isolated, anecdotal experience and not at all a valid test of impact resistance, but I have been a believer since then. Just buy them when they are on sale.