I know nothing about mirrors other than the obvious (?) But I built my
boat's windshield with 3/16" tempered glass. A local glass co. cut the
pieces from what I understood was regular glass then sent the pieces off to
be tempered. It was not expensive, only adding maybe 50 bucks to the job to
have it tempered. So if you want something stronger than plain old glass,
look into getting some glass tempered then silvered.
I did shop around for this job as some companies e quoted outrageous prices
but I ended up with the job done reasonably.



--
Ron White
Boat building web address is
www.concentric.net/~knotreel