I have the following PS1 demo discs for sale/trade:

Titan AE demo w/ sleeve - excellent condition/unreleased game.
Interactive Sampler Vol. 3 (ver. 3.5) - with sleeve, great condition
PS Underground Demo Disc Ver. 1.4 - w/ sleeve, excellent condition

Pizza Hut discs:
Disc #1 - Green, loose
Disc #2 - Blue, w/ sleeve (top is torn from being opened)
Disc #3 - Pizza Powered Give-away disc, loose

All of them play fine, despite the pizza hut ones being a bit scuffed, although i must say that Disc 2 of the PH demos freezes when loading Tetris as it has a fairly large scratch at the bottom. The official PS ones look and play great.