There are a lot of good sunglasses on the market today, a person can find high quality glasses for less than $300 too. Technology on lens making is far better than 20 years ago and a set of $75 glasses will meet the optical purity of a set of $300 ones. And since all sunglasses for cycling the lens are made of plastic they are very susceptible to scratching so buy a pair that have replaceable lenses because you'll be replacing them. I did something a bit different since I got tired of scratches, I went to Costco and my vision checked so i could get a pair of glasses on discount through work, my eyesight was 20/20 so they corrected it to 15/20 which allowed me to get the Transitions DriveWear glasses, these glasses are the best sunglasses I've ever owned and the scratch resistant coating is superior to regular sunglasses, I wear these on bright days, on cloudy/hazy days I wear my Tifosi Fototec glasses which are due for lens replacement, but these are very good glasses, when I compared them to Oakly I could see no difference in visual purity, the Tifosi cost as much as an Oakly lens replacement, and the Tifosi lens replacement is about 1/2 of what Oakly replacements cost. At night I simply wear a pair of clear safety glasses I get at home improvement places (I do have to check several different kinds since the cheap ones tend to visually distort things especially at the sides). I have another pair of dark (they start out dark and get darker) photo polorized glasses I bought years ago from Bolle that were supreme at resisting scratches and supreme at sun protection (I lived in the desert so having very dark glasses was essential for me), those were made of some sort of laminate glass lens that was highly scratch resistent, I can't count the number of times those things fell and hit rocks etc and never even a pit, but I can no longer find those anywhere or I would have bought those again, the frames got too stretched out over the years to stay on my face while riding, so I use them when I'm fishing on very bright days because those are darker then the ones I got from Costco, but where I live now in Indiana the brightness of a normal day isn't as intense as it was in the desert so the Costco glasses work plenty good enough for riding and driving.
I just don't think, after trying many different brands, that the expensive ones aren't worth the money, they are only worth the money if you want style points.