It sounds like you're saying if the glass attached to the helmet in some permanent fashion it's more prone to breaking. I can understand that. What about double-sided foam tape? That might dampen vibrations enough to prevent them from being damaged.Even if the glass is heat or chemically tempered, it would shatter/crack if the helmet gets hit the wrong way, or if it is dropped.
I would be happy just to find any decent replacement lenses for my Rubies Vader that I am in the process of modding.
I would be interested in some good TK bubble lenses that DON'T give you fish eye. Anyone make those?