Stern SS machines are under rated.
Paragon and Fathom are considered the two best Bally machines and the most commonly requested. But Stern's of the same era are just as good. Of all the games I've restored and sold, I really miss Meteor and Galaxy. I would buy another Meteor in a heartbeat - as a keeper. Another title that is under rated is Flight 2000.
Also - Bally EMs. Especially 4 players. All the EM talk has been about GTB Wedgeheads and drop target games. Four years ago, I started collecting 4 player Bally EMs, and never looked back. Bally Wizard, Old Chicago, Fireball, 4 Million BC - all great players.
mate... mate... mate... what are you doing?
I know Bally EM's are underrated... as are 60's WMS games... but this means you can pick em up relatively CHEAP cos everyone is chasing GTB games! You keep telling everyone and they'll be in demand and so the price increases... dear oh dear... put the cat back in the bag!