Three ways to go:
1) buy cheapos and don't worry about 'em
2) buy $50-70 polycarb polarized and try to squeeze 2 seasons out of them
3) buy $150-250 and enjoy the best there is in featherlight titanium polarized technology
For the last few years I've been a "2", averaging 1.5 seasons per pair. Frankly, it's very economical (good price/performance) but there are two tough things about it:
- it's hard to find good glasses at mid cost
- you need to take care of them or they will be toast in short order
Bolle's are often available at this range at REI/EMS, although it sounds like Lefty got them at "level 1" prices. Costco carries a polarized polycarb at ~$70 with titanium frames that are su-weet and I am thinking about them for a next pair.
You need to keep "type 2" glasses on a loop around your neck or they will get destroyed. Never wipe with paper, like glass, only soft cloth. Those loops are the biggest single contributing factor to scratch-free polycarb lenses, in my experience anyway.
AND THEN... I saw the top of the line Action Optics and tried them on... then the Maui Jims at Concord Outfitters... suddenly I am thinking hmmmm.... maybe I am a "level 3" kind of guy afterall. Hey - Father's Day is coming up!
My last $50 pair are still doing great (18 months old). I suspect that I will be buying another pair mid-season. They will probably be "3" (first time ever for me).
Experts say pick copper lenses for fishing. I can't wear amber cause I can't see the brake lights in front of me when I do. I use grey lenses and seem to be able to see fish in the water pretty damn well, almost invariably better than the folks I am fishing with.
I wear polycarbs because my brother the eye surgeon convinced me to. In eye trauma, it's often the glass splinters that do the most damage and polycarb doesn't shatter. That's not to say shatter-proof glass isn't great, I am sure it is. Like many things it's just a choice you make.
The safest glasses are the ones you wear most often. Choose a color and model that you will wear every time you go.
Like Nick said, casting as the wind predicates is the biggest safety factor of all. Keep the wind blowing away from you on the casting side.