The thin plastic film is laminated inside the glass (think like an oreo). I would think glass condition (as far as scratching) is largely impacted by the previous owner's care regardless of location. If someone's driving around with worn out dirty wiper blades, those'll be harder on the glass than someone who keeps theirs in good condition. I see cars come in to the shop where the thin part of the wiper blade that's supposed to do the cleaning has just plain torn off and they're oblivious to it.