This is just my opinion but I only use 4mm glass because unless you have a 12 foot Scrub python that likes to hit the glass you don't need 6mm. 4mm is more than strong enough for almost all smaller applications, my largest I use it is is around 1200 x 500.
My bloke just arris's the edge, don't waste time and money getting it polished, all he does is very quickly takes the sharp edge off, for nothing.
My bloke just arris's the edge, don't waste time and money getting it polished, all he does is very quickly takes the sharp edge off, for nothing.