Folks,
Frank is spot on here!!!
Back in the G.O.Days, when Dr John Colvin was the head scherange eyeballs for the RAAF and civil by whatever name at the time, he used to conduct the most graphic eyeball health lectures.
Anyone who attended one of these lectures, was never the same again. All the "glass" sunglasses went, and polycarbonate lenses became the order of the day. All of a sudden, nobody I knew mowed the lawn without safety "glasses".
Every featured person was an ex-pilot, having lost an eye under circumstances where proper eye protection would have prevented the immediate cessation of a professional career. Some really gruesome results from very ordinary and commonplace accidents --- in the cockpit, in the car or around the house.
Cheap insurance !! Do you really want to gamble your career for an "image". No, nil, none, zilch glass lenses, if you are smart.
An added bonus of optical polycarbonate lenses is that they are actually more scratch resistant than optical glass.
Don't forget, proper sunglasses also delay glaucoma causing damage from the in-flight environment, quite apart from preventing physical damage to the eye.
Tootle pip!!
PS: Beware the market flooded with pirate Ray-Bans and Randolph sunglasses, you cannot tell from visual inspection, but the glass the lens are made from is really nasty stuff, with little impact resistance, and shatters in to shards.