I went with the Polycarbonate 580 in grey. The pair I lost was the 580 green mirror glass (great for tannic water). I think the glass was a little clearer, but it may have been the green mirror that made the tannic water look good that I fish often.
The Polycarbonate is allot lighter and you can tell the difference when wearing them all day. And I like the fact that if I’m running down the river they have a better impact resistance rate. I also saved a little chunk of money, so over all I am happy with them.
I would buy either one again, the glass or the Poly.
And I also bought one of those goofy looking straps, that I will never call “goofy” again!