The Bally class of 1981 is tops. Plus Xenon as a November 1980 game was in arcades with all the other great titles. They were so good, Centaur was re-released and EBD was done twice. Then came another Fireball. Why did Haggis pick Fathom? Because it's an awesome game. Plus the ease of restoring them with the great selection of boards, displays, stencil sets, PF's and BG's is great.
That's why Bally & Stern classic SS games are consistently increasing in price. The fact the same board set (except sound) basically works in every game from 1976 to 1983 is unmatched by Williams and Gottlieb.