Black Hole is the complete SS package - lots of good shots, lots of targets, brilliantly implemented multiball, balanced scoring. Achieving a good multiball starting downstairs, then the switch to upstairs three ball is really well done rule wise. Despite the large window area creating an open playfield, the game does not feel like it has unused territory.
However, you said *only one*, so I am going to put Firepower up for the SS though - great theme, great layout, great sounds and voice calls. Like Black Hole it was ahead of other games by a long margin - between games on DMD's and back to this, it does not feel like an old game. Getting multi-ball is not easy - can be challenging and frustrating as it seems to last only seconds a lot of the time. But it keeps me coming back, more than any other SS I have or have owned.
For EM, I played a few when deciding, like you, to get one EM to round out the collection. I started playing at the tail end of the EM era, so had a soft spot for some chimes. It had to be a Gottlieb Wedgehead given they were pound for pound the leaders of the era. Ultimately I settled on King Pin as I recalled it from a milk bar on my paper round as a kid, and love the layout - wide open "bowling lane" to the ten "pins" (drop targets). The little "Frustrator Flippers" as I like to call them up the top are both annoying and fun at the same time. The game play is reasonably fast too, and rather challenging. Round one is a score round, and when you get the ten pins, round two offer a moving 5,000, and then if you get to round three (rare for me), a moving special to collect which is really satisfying. Only trouble is that the theme doesn't really appeal to me as I am not into bowling (and I have resigned to the fact that I am somewhat one dimensional with pinball - if it's not sci-fi I don't enjoy it as much). For sale at the moment
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