They look bang on I have to say, even the lense etching is there.
I think I'd just worry a little about what would happen to the lense if you got unlucky with a stone from a car or whatever.
I think my oldest set are about 3 years old and still going strong! Lost one pair on top of the Galibier whilst doing 40+mph and left them behind because I'd got a years use out of them for £15.
I'll be riding out side a lot more this winter, just grabbed an Exposure Race Mk12 for £150 using cashback payouts + top ups + cashback.