I use the thin rubber gasket on my MP40s on red sea XL300 tank. I've never had one fall off.Wait, the thin gasket is for thicker glass? That seems counter intuitive, I assumed it was for thin glass to minimize the magnetic effect.
My glass is 3/8" and my mp10's (no gaskets) struggle to stick. I find a wet side in the sand once a month or so. Mp40's would've been a better move.

