Well I've had a chance to print three plates and three single parts, and the etched glass with slurry is working quite well. It holds well without being hard to remove the part after printing. I think I may try printing without slurry again and bumping up the heat to see if that helps with adhesion, it would be really nice to not have to use slurry.
The durability of the glass compared to window tint is apples and oranges, unless I break the glass I think it's going to last a long long time.