Those home games can be fun but some of the parts were specific to the games and can be hard to replace/repair if they do. read through the ken layton post you posted on for a good feel of how they go.
Agree with CT - I'd buy a nice one but only for under $200. Remember, you can get a completely working, fun, playable, serviceable 70's/80's solid state pinball for $500 and there's a lot of support out there for it - parts and knowledge. If you have any DIY/repair/soldering capability that is a fun way to go. That skill is necessary for any level of pinball ownership however, even home models. Unless you live in the chicago metro area, there are not a lot of repair guys around.