I've never tried the costas, but I've worn nothing but Serengeti Drivers since around 1988. I lost a pair, broke a pair, and have worn out several others. My current pair is probably 6-7 years old. The drivers lens is amber and filters the blue spectrum. I can see farther through the fog, snow, rain, and woods (big difference in the fall when everything is brown and blends together) with them on than I can without them. I can see deeper into the water as well. Don't let the Internet prices scare you, I bought my last 2 pairs at wal-mart for $45 & $75. I stopped in for a replacement screw for the frames last summer, and the lady informed me I had just missed them on close out for $15 per pair.
Put a pair on and you will be hooked. Just make sure they are the "drivers." I've never tried the other lenses, so I can't vouch for them. I know this sounds like a commercial, but I really like this product. If I lost/ broke mine today, I would have them replaced with another pair tomorrow.