I have both Smith and Costa and prefer the Costa 580G over the Smith Polychromatic. I think the clarity is better on the Costas and have never had any issues with them. Smith on the other hand, had some micro-bubbling on the polychromatic lenses (both sides) so I sent them back and replaced them with different polarized lenses...no questions asked. Thumbs up to Smith for that!
At the end of the day, both companies are top notch.
I am the one who did that interview, and it actually led to a series of additional interviews culminating in an article which is coming out in the next American Angler magazine.
I think there's some good information here and possibly some bad information.
Regarding weight: this has more to do with size of frame and lens than with glass versus plastic. Glass is a little heavier but that is more noticeable on bigger frames. I have a pair of glass Costa aviator-style glasses and a pair of super lightweight blade-style Smiths that I run in. I don't personally notice any difference.
Regarding quality level: the Costa 580 Silver Mirrors in glass are my personal choice as the best all-around lens, but lens choice is subjective. Most people I have put those lenses on do tend to agree. Costa says the 580 business is due to a formulation that deletes the 580nm part of the visible light spectrum, which as I recall gets rid of yellow light.
One thing I have learned talking to sunglass companies for many years covering this industry: they have more jargon and are less forthcoming than any other product sector. I am not sure I believe anything I hear from any of them, because what they do is highly technical and dumbing it down for a lay audience may render it less than completely accurate. However, in my experience, the Costa 400 series is similar to the Oakley polycarbonate and to the Smith polycarbonate glasses. 580s are more expensive than any of those three options and I think they do represent a quality upgrade, particularly in glass. I say that based on fishing and wearing all three companies' lenses for a long time. Your mileage may vary.
Smith is the only company to offer the photochromic lens technology and it is pretty cool. As I recall it is based on silver halide and works similar to old school film, except the "exposure" chemistry can be reversed. As you go into the sunlight the chemical reaction causes the material in the lens to darken, thus cutting light. It doesn't affect polarization quality but it can be very useful, especially in a light-color lens meant for early morning wear.
Oakley has done a good job of focusing on the ballistic protection aspects of their lenses and serves a lot of military contracts. For eye protection purposes they are probably the most extensively tested if that is a factor for you. I have also personally witnessed Oakleys being wholly manufactured in the United States at their factory in California. I believe both Smith and Costa import their glasses, if that is important.
Good luck with your choice,
Zach: Great to see you on the forum, I'm a big fan of The Itinerant Angler!
For me, it's Costa 580G every day of the week. I love the blue mirror for open water, green mirror for shaded fishing, and silver mirror for all-around. The thing I like best about Costas is their mirror lenses still perform in lowish light situations (not dusk, but sun behind the mountains).
Smith's weigh quite a bit more and clarity isn't even close...
You should try them side by side sometime...
I agree they likely are the two best, but man the Smith's feel heavy on your face in comparison to the Costa's and I personally see much better with the Costa's that may be different for others though as I am sure everyone's eyes are a bit different.
I have owned both Smith and Costa for the last dozen years. I've always thought that Costas felt much heavier, when doing a side by side comparison. I love em both, but like Smith better due to the style and lens tints (and weight)... Polarchromic copper can't be beaten IMHO unless on open water, then both companies make a blue mirror glass.
I recently had some buddies try on my Smiths next to their Costas, and they absolutely agreed that Smiths are lighter than their Costas. Both guys on that trip got home and ordered Smiths... I don't mind telling you that one of these guys is NEVER wrong
I am crazier about shades than anyone I know personally, have nine pair at present for work/fishing/active sports, etc. (hey, some were gifts ). I can't leave the house without em, cursed with very light eyes that are extremely sensitive. For that reason, I always take two pair, especially on a boat for a long day... My costa 580 green Howlers and my polarchromic copper mirror Smith Chiefs. When it's super bright, the slightly darker costas can be nice. Usually take my Revo Water lenses too, actually... Wedding present from the wife for our tropical honeymoon, so I love em, but their poly scratches easily
Smiths have some serious style to boot... I guess Costas do too, if you're a frat boy anywhere from TX to NC
Kidding, kidding... No need for anyone to get upset, just a little joke here down South (and I was once that kid). Hey, I wish every floppy-haired college kid in that swath owned a product that I made, I'd be fishing right this moment instead of talking about shades!!
I've read all I can find about sunglasses, colors, etc as I am going to take the plunge for an expensive pair again after many years in a month or so. I've got to go in for a cataract consult in a couple weeks.
The biggest puzzle to me is the near universal opinion that blue/grey is better for offshore use than copper/brown. Perhaps I just need more time looking through blue/grey to adjust to them, I don't know.
But while plagued with ocean tally worrying ballyhoo teasers off the reef, I have switched back and forth with a buddy's blue grey Costa's and my $8.00 Chinese plastic copper/brown glasses, and the latter won hands down for spotting them instantly. So for me, regardless of where I'm fishing,, world class blue/grey lenses are worth less than $8.00.
Perhaps it is just my eyes, which are brown surrounded by green, I don't know. Or perhaps it is just because I have used brown glasses almost exclusively since discovering polaization as a teen, and my brain is now hopelessly hard-wired for that light bouncing around inside my skull.
It seems to be the same as with fly rod preferences - try before you buy - though that is pretty difficult for fishing unless you trade off with a buddy - and doubly difficult if you wear corrective lenses.
Up to 10% of us are "color-blind" to some degree. Soooo, if you don't benefit from the same color of lenses that someone else does to the extent that they do, it is highly likely you perceive colors entirely different than they do and will have to find what works for you.
I am one of those color challenged folks and what I see is very different from what the majority of other people see.