I am getting ready to spring for some Rx Maui Jims. The price difference between glass lenses and polycarb (?) or whatever it is is about $40. Glass being more expensive. Glass has better optics, and more color posssibilities, but poly is less fragile. I probably would use these mostly while driving, some beach time and walking around etc. Is there really a compelling case for one vs. the other? Especially if you are not going to put them to heavy use i.e. golf, extensive beach time, etc?