IMO, they aren't worth it. I have a pair of Valentino aviators that my sister got me from Neiman Marcus and this pair I got at a thrift store, and I can't tell any difference, quality-wise. Sunglasses and smaller accessories are how big-name brands make real money, next to cosmetics, by being able to reach a broader market than, say, the clothes. And for some reason, most people are ambivalent of buying designer clothes, but aren't hesitant to buying expensive designer accessories. I just don't think they're worth it, but if you do and you're happy with them, then congrats