Hi.
I need new glasses. I am conflicted over the options available for lens material. 
My concerns are scratch resistance and long term clarity.
Many years ago I had some sort of plastic or polycarbonate lens with a coating and I had scratches within 30 days. Fortunately I had a 30 day return option so I swapped for glass and had no problems. Fast forward (really) a decade so what do I do now with new materials available?
I would appreciate personal and professional experiences. Thanks.
Yes, plastic lens are light to wear, but prone to get scratched even if it is polycarbonate lens with scratch-resistance coating.
Years back , I had a pair of presciption eyeglasses with polycarbonate lens plus coating from Costco which warrants for one year. Me being a sorta rough user, the lens was scratched & I got it replaced with new lens no charge even just after one year. Excellent customer services from Costco!
Only a few months ago, I had a new pair of eyeglasses of a new prescription from Lenscrafters on special sale. Again with scratch-resistance coating on it. But I did not buy the $25 replacement warranty.
I got it scratched on my vacation trip. So I went back to Lenscrafter to replace it. I got the lens replaced & was only charged $25 instead of the full price. Why? I was allowed to add on the $25 replacement warranty which I did not buy at the first time of the eyeglasses purchase. Another example of excellent customer services.
c-J