My lightwedge sounds just like BBRags--lightly frosted and it does make the text a little bit less crisp. But I do really like it. I use at night quite frequently--and just increase the font size.
I haven't had any problems with scratches, and I've been able to clean the dust off very easily with those lens cleaner cloths for eyeglasses.
I keep my reader in the light wedge cover all the time and don't do anything special for storage--it resides in my purse most of the time, unless I'm using it.
dordale