Found a few more dual-versions. Let's do a little analysis:
1976:
Aztec (EM 10,050 - SS 10)
Black Jack (EM 120 - SS 4,883)
Evel Knievel (EM 155 - SS 14,000)
Freedom (EM 5,080 - SS 1,500)
Grand Prix (EM 10,554 - SS 5)
Night Rider (EM 4,155 - SS 7,000)
Of these, Aztec and Grand Prix were solid-state prototypes and thus very rare. Not likely to ever see them and not really worthy of comparison. I love Bally EM's from this period and vastly prefer Freedom in EM than SS. Same for Night Rider. So I'm guessing the other EM's are also the ones to get... which makes Evel Knievel and Black Jack the rares of the bunch.
This was the last year EM's were being cranked out in huge quantities by all manufacturers.
1977:
Cleopatra (EM 1,600 - SS 7,300)
Hot Tip (EM 1,300 - SS 4,903)
Mata Hari (EM 170 - SS 16,260)
Pinball (EM 594 - SS 1,654)
I prefer Cleopatra in EM format, but Pinball in SS because the EM version is Chicago Coin hardware... blech. Very keen to own a Mata Hari EM. Anyone have one for sale? *grin* Not enough experience with Hot Tip to call it either way... but with those production numbers either one is reasonably attainable.
By 1977, only Gottlieb continued to crank out EM's in high volume. Everyone else was jumping ship.
1978:
Charlie's Angels (EM 350 - SS 7,950)
Close Encounters (EM 470 - SS 9,950)
Dragon (EM 507 - SS 6,550)
Joker Poker (EM 820 - SS 9,280)
Sinbad (EM 950 - SS 12,950)
Now it gets interesting. Gottlieb soldiers onward with EM's, but we are finding new desirable features in their SS versions... including the bonus option of preserving the original chime bars if desired. Which is why JP and Sinbad SS versions win here for pure gameplay in my opinion due to the extra features and vintage sounds. Not enough experience with the other three... but I bet they also follow suit. Yes?
By now, SS had totally taken over and Gottlieb only built EM's in the hundreds. A few EM's squeaked by which were not produced in SS versions and are thus among the most sought-after: Gemini, Hit The Deck (and AAB variants Neptune/Poseidon), Rock Star (and replay version Blue Note in early '79), and Strange World.
1979:
Solar Ride (EM 365 - SS 8,800)
Space Walk (EM 215 - SS 9,899)
Never seen either of these EM's... very rare. By this time, Gottlieb must have been building EM's to use whatever parts they had left over. Only a few titles made and only in the low hundreds at that. T.K.O. was the only new, unique EM released that year... production run of 125.
Thus endeth the reign of EM's. *sniff*