I have the Costas in poly and the Action optics in glass. Both RX. I used to wear fit overs. When you spring for the RX, it will rock your world(that's a good thing). Really, they are that good.
I like glass becuse they are less likely to scratch. Now I also have the poly carb, and they are lighter which is also nice. The glass has better optics. I don't think that glass RX polarized lenses will "shatter"(the glass sandwiches a film of polarizing material), but as a surgeon, I'm sure that Juro's brother has seen all sorts of things.
Action Optics does bi focles. Call you local dealer and ask them about it. You will never go back to fit overs.
I need RX, so I have given this a lot of thought and tried most every thing. Juro, you have developed a good eye for fish, but I don't think that most people will benifit from Grey lenses. Vermillion, copper, amber, brown, yellow, are provide better contrast. Unless you are trying not to rear end that car in front of you.
Wow, we have ammassed quite a data base regarding Fishing goggles.
One cast can change your day...maybe your life.