I have a pair of wiley sg1's there good although they steam up like hell on climbs!! US military use them, I seen some interesting pictures online showing how good they protect your eyes.
I wear contact lenes and it hurts like hell when i get dust in my eyes so I bought these after seeing them on the gadget show. But the constant steaming up and goggle like looks I've ended up ditching them for endura stingrays.
I got my wileys off ebay from U.S. about 50quid i think.