hi alex
With some helpfull advice from mark I used it on my 12" gso without a problem.
My cell is a bit of a mess as I changed my mind a few times while makeing it but the velcro works well
You can see some edge supports there , they don't actually do much , barely touch the mirror
I put them there so i could remove and replace the mirror in the same position ..The velcro seems to have a fairly passive
hold on the mirror in that i can easily lift it a little in the cell ..but at the same time its fairly difficult to seperate it
So much so I clean my mirror in the box these days.
In shear or upside down I couldn't see the mirror ever falling out .. .. would a full thickness 6 :1 mirror work in this arrangement mark?.. mine is quite heavy ..and I could imagine a 2" being heavier still.