Acrylic clarity is supposedly better than glass, but I've never noticed any difference myself. I've heard that silicone doesn't adhere to acrylic, but have not tried it. I'm sure there's probaly a way to use it. Since you got such a great deal on that, I'd not give up on it too easily. 3/4" acrylic is very expensive, typically. I just checked my online source and a piece like that new is $200.