I'll play.
1. Centaur
2. F-14 Tomcat
3. Superflite
I'm sort of surprised to be the first person to mention Centaur. I have a love hate relationship with mine. It died on route, while I was trying to sell it. Then I tried to sell it again broken. And now that I finally got it really working again, I feel like an idiot for trying to sell it. The game is everything I love about pinball wrapped in a heavy metal original theme.
I also have been trying to figure out if I want to part with my F-14. I have a Getaway too. I don't think they both belong in a collection the size of mine, but I can't really bring myself to pull the trigger on selling one.