Nope, but sure as hell going to listen in on this thread!
Thought about lexan - it scratches when cleaned in the field...
Thought about tempered glass - but it shatters into pieces when dropped and cant find it in the right thickness...
Looked up Sapphire - cant find it anywhere in Aus, because were at the *** end of space!
So I am basically looking at glass of some sort, just for strength and scratch resistance and optical transparency - and yes I am thinking of a security window film on it for strength...