A single bug strike or accidental drop has ruined all the cheap sunglasses I've ever owned. Even though I treat my Oakleys more carefully, stuff like that has happened to them, yet the optical quality has remained excellent. I also recently bought clearanced Dragon Alliance sunglasses ($30 for a MSRP $130 pair) for off the bike, and though they look just like the kind of free sunglasses brands give away as advertisement, the visual quality is leaps and bounds superior. Both Oakley and the Dragon Alliance lenses offer increased clarity to a degree that I notice, as I'm slightly nearsighted but don't use corrective lens with sunglasses. I will probably get an Rx for my low light Oakley lens soon as my night vision could be better. Can't do that with cheap sunglasses.