Yeah, hard to imagine any shades being more fragile than Oakleys. So I can't agree w dave's durability argument, except that you will be much less likely to put them where they might get sat or stepped on after paying 3 figures!

The protection of complete UV blocking (and IF and near blue spectrum preferably) and reduced eyestrain from optical quality lens are important IMO. "worth protecting, worth Bollé" was a good slogan. Bollé used to make a big deal about the absorption spectrum, the IREX lens filtered all UV and IF radiation, now their literature doesnt say what % visible, etc. are transmitted, I guess they are still good.

When I worked in a lab, I put a lens from my Bollés in a spectrometer and it showed a beautiful bell shaped curve around the visible spectrum. The transmission spectrum of a cheap sunglasses' lens looked more like OJ's polygraph!