You know, I have to say, having no scientific data behind it but I do think the better optics make a difference in the long term. I've had cheap glasses and expensive ones and while there is a point where beyond it you are paying for marketing, the more expensive lenses will have better optics which means less eye stress and strain. Now I only wear glasses with good optics. That doesn't mean you have to pay a lot, just find the deal. I fiigure that even if I am wrong, I figure what's my vision worth? In the end its worth more for good sunglasses.