Nxt, julbo = great - Julbo Instinct Zebra-NXT Photochromic 2-4 Antifog Speed Sunglasses

NXT is the stuff. I've had these glasses for over a year, wearing them falling down ski slopes, hiking through dust storms, and being dropped on floors, thrown in pockets & center consoles with no case, and all they have are a few minor scratches. No poly could do that, only glass with added weight and shatter-ability would do better. Lenses never popped out, frames never deformed or broke.
They photochrome as advertised. I haven't dont any l/r comparisons, but clarity is about on par w poly, not as good as glass of course.
Pros: lightweight, scratch resistence
Cons: clarity not as good as glass

This review was written in the old system and had content requirements that are different than reviews written today.