You should look into getting some Kaenons...the Kore model are probably the best pair of all around sunglasses (I have the medium size with Copper 28 lense- very versatile with varying light conditions)...lenses are clearer than polycarbonate lenses, wrap around design eliminates glare and wind, lenses have a water sheeting layer, extremely lighweight and comfortable ( forget that you are actually wearing sunglasses), rubber temple and nosepads keeps the glasses in place, top of the glasses are curved higher so sweat from your eyebrows will not bead and run down the glasses, 2 layers of polarization, the back of the arms curve down so they don't interfere with wearing a hat, etc...I can go on and on about these. I am a very big fan of sunglasses and know alot about them. I have worn everything from Oakleys, Maui Jims, H2Optics, to Serengetis and the Kore outshines them all in functionality and performance on the water. Go to www.kaenon.com for more info. Apparently, alot of the pro anglers are endorsing these and I don't blame them. However, I have not tried the Costa Del Mars but eventually will since I have heard good things about them. Everybody's finances and preferences differ, but my advice is to buy the best pair that you can afford...your eyes will thank you and your time on the water will be more enjoyable. Glass lenses are clearer than plastic lenses, but the caviat is that they are heavier. If you are fishing freshwater, buy copper or amber lenses...it will give you better color contrast, depth perception, and sharper details which helps when sightfishing. Grey lenses are suited really well for saltwater fishing and the color spectrum of the ocean. In any case, when buying sunglasses, keep in mind some of the things mentioned above and if the glasses will satisfy the purposes that fit your needs.