I asked some of the same questions and looked for recommendations a few months ago here and at another chat board when I thought I had lost my sunglasses. The overwhelming response was to get a pair of Smith Action Optics glasses.
Now I don't have any kind of logo on my shirts (except a Steelers t-shirt or two and possibly some dried pizza-sauce that might be confused for an alligator) and my $50 fly rods probably wouldn't put me in most elitist circles. I'll be "reasonable" when it comes to most equipment and clothing (waders, fly lines, vest, etc) but 2 areas I figure I should invest in would be personal safety (good wading staff) and my eyes. I don't have any specific data (although I guess I could find a ton of research on Google) but I feel that a good pair of glasses are better for your eyes in the long run than a cheap pair so I purchased a pair of Smith glasses. Funny thing is - I found a pair on one of the online "closeout" websites for over $100 off normal price so they became "reasonable" too.
As they were closeout I didn't have a choice in lens color and got Brown. I've heard many people say Copper is excellent. My other glasses (which I found later btw) are smoke gray. Do the Smith's work better? I think there's an improvement and I'm very happy with them but again, I didn't buy them so much for their glare-reducing qualities or ability to see into the water; I bought them to help protect my eyes.
I have no experience with the Costa Del Mar glasses.
YMMV
Take Care ...
Steve
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