Dave,
I would so worry that by using "cheaters" for an extended period of time, whether magnifier glasses or sunglasses, that harm would/could be done to your eyes.
I'm not an optometrist, or an optician, or an ophthalmologist, but I really feel something as special as sight should be cared for by a professional. They're (your eyes) worth the investment.
Betty
Trouts don't live in ugly places.
A friend is not who knows you the longest, but the one who came and never left your side.
Don't look back, we ain't goin' that way.