I had a glass desk, I hated how dirty it would always look. I also had other problems with it because it was less of a desk and more of a cart. I almost shattered the glass and sent my monitor crashing to the ground more than once when I had it. make sure those bars that the suction cups are on are in real tight and can't roll around on you, because they would roll and nearly drop the glass all the time.
also, I have a corner desk now but I don't face it towards the wall.
I love having a wall behind me while I'm on the computer, it ensures nobody can sneak up on me if I'm doing something I don't want other people to see or whatever.