much of a muchness to me. I love working on all manufacturers. Gottlieb were simple and reliable (70's) - plenty of space to work in. The Drop Targets were a pain to work on, but the score motors etc were more "logical" and schematics were easier to follow. Ballys were better than Williams. Williams four player machines and the player unit / coin unit were an absolute pain to work on at times. However, once "tuned" they were ok. Bally SS blew away the williams - just look at the drop target and flipper assemblies ! Gottlieb sys 1/80 were just like the EMs - except with no room to work and WAY too much going on. Gottlieb "over simplified" the design. They made some awesome machines, but under the bonnet became a bit of a nightmare. System 3 machines are the most reliable, so not much time is spent under the hood. Except for the flipper assemblies. Bally / Williams are ok - depends on the game. Sterns are similar to Bally / Williams. Data East have an annoying GI system with no plugs. Soldered straight onto jumper boards. A real pain.