Hrm, 20 bux for Zaggs which seems to be probably the 3M stuff (which I know is tough cause that is what skinit uses and I have had a skinit skin on my macbook for like 1-2 years and not a scratch on the skin itself even. Plus it has not tried to peel off at all. They claim it also comes off with no residue but since I've never wanted it off, don't know). Plus I don't have to use water to apply it.
But 7 bux is significantly cheaper. Sadly, what really has me more going for the 20 bux is I already know it's probably good and I don't have to use water to install it (I don't care what that webpage says, particularly when installing on something so small, I don't like the idea of applying a wet item on my ipod).