I used to sell sunglasses. With that said, IMO Revos are the best glasses you can buy. Sure, you could spend more by getting custom frames and lenses, but the quality will not be up to Revo's standard. Revo uses glass lenses, a must in any high quality optics. A polycarbinate lens (ie. Oakley) - plastic - cannot compete with glass in terms of clarity. However, polycarbinate is MUCH stronger than glass. If you are using these glasses for active sports, having a glass lens could be dangerous. If you ride a motorcycle, NEVER ride with a glass lens - polycarbinate only! Oakley's poly lenses will stop a 12 gauge shotgun blast from 10 ft. - (of course that won't protect the rest of your skull) - but you get the idea. Any impact like that would shatter a glass lens, sending the glass shards right into your eye.
Now back to the clarity issue...Revo uses glass lenses. So do many other higher end sunglass manufacturers (ie. Maui Jim, Ray Ban, Serrenghei, ect.). However, Revo polishes their lenses to the same surface quality standards that NASA uses for their telescopes! I have owned a pair of Revos for 8 years. Yes, the lenses are slightly scratched from wear and tear - even after keeping them in their case at all times. Scratches will happen with ANY sunglasses. The slight scratches do not impede my vision though. Revo's frames are sturdy metal with changeable arms and nose pieces - more easily repaired in case something gets stepped on, bent, broken, ect. Revo offers polarized lenses - a must for being around water.
I've tried on zillions of pairs of sunglasses in my day. Bottom line, nothing compares to Revo in terms of optics/style/quality. You'll pay more, but IMO they're worth it. Take care of them, and they'll last a long time. If you're the type that loses sunglasses regularly, buy a $10 pair and save yourself frustration and cash.