I have Maui Jim's with glass lenses, and, yes, they are heavier. But when I was doing the research about which type of lens to buy, I read that it is impossible to curve polycarbonate without distorting the lens material in the curve. For some, that may not be a deal breaker, but my eyes seem to be very sensitive to lenses with imperfections. I can put on a pair of sunglasses and my eyes and head will begin to ache within a matter of seconds if the lenses have any distortion in them. That's why I don't buy $20 sunglasses. So, I buy expensive glasses and take very good care of them. My current pair are 10 years old.