I don't buy into the premise of your question that certain games are a good value. In general a Stern pro may be a good value but you never know what you are going to get or how your playfield will look after 1000 plays. I also have much different taste in titles than you do so that part of the question is useless.
The answer to your question is build a network of pinball friends, always be on the hunt, gently bring it up in conversation with people you meet because almost everyone knows someone with a pinball machine stashed somewhere. The real value game then becomes the one you find a good deal on.
If you hunt for certain "value" titles you will quite likely end up overpaying.
Lubbock, TX
