When Atarians came out I thought it was the coolest game ever. Great colorful artwork, widebody playfield, computer generated sounds. Hell, even the coin slots were cool.
Actually, I think it was just my endearment of the Atari 2600 that allowed me to instantly like Atari pins. Middle Earth was another nice looking game and its unique playfield layout was enticing, but as barakandl said, gameplay is BLAH.
Right after high school a friend and I started buying cheap pins. We bought a Space Riders -- another good looking game with its mirrored backglass. But if ME is BLAH, SR is DOUBLE-BLAH. Couldn't sell it fast enough.
From what I've played, Superman is the best. Wouldn't mind playing one again some day.