I have a Time Machine and for the novice player it's really a blast. Great music and really draws them in. But if you have a memory of Tales from the Crypt, and want to have something more challenging, TFTC is a better game. That being said, just how clean is the Time Machine? If it's REALLY nice it would warrant the $2500 asking price. It has to have PRISTINE ramps and fantastic playfield with next to no planking. Backglass has to be original with mirrored finish, cabinet has to be fantastic.
You normally see a 6/10 to 7/10 TFTC for 3000-3500 on Pinside and other sources. I'd love to have one at some point, and have other DE games. Just haven't had the stars align yet.
Good luck with your search! Agreed at $4500 for the pair, IF WORKING, I'd do it. Top flipper in TFTC could be a busted wire or bad or maladjusted EOS switch (did they use those in TFTC?)...