Great question...
Let me do a little investigating. I don't have any end-user notes on the Snail at all yet, so it may take me a day or two to find a few hobbyists who use one regularly.
If no one has tried thicker glass yet, I'll cajole someone into making a test out of it. One way or another, we'll find out if thicker glass is manageable.
I'll post back with updates as they arrive.
Thanks for your patience, and let me know if there's anything else I can do for you!