Stern had a big party celebrating that ACDC had become their best seller. It's been estimated their previous best sellers were POTC and LOTR at around 7000-8000 units. So, even without the actual numbers - you can get a good estimate. Some way-to-low guesses so far.

Not necessarily. By saying "modern", that excludes older games entirely from comparison.

It came out before prices went completely apeshit. You could get a Premium shipped for less than $6k. That & the giant Angus face drove people to the Premium. I feel like AC/DC Premium had WAAAAAY more differences than the Premiums that came after it. Compared to the Pro, AC/DC Premium had:

-All LEDs (until the LED Pro)
-Swinging bell (until the LED Pro)
-Color changing GI (first time on a Stern)
-Some Color changing inserts (first time on a Stern)
-AC/DC drop targets
-TNT drop targets, revealing a standup
-TNT plunger movement
-Dancing band
-Crossover ramp
-Lower playfield
-Molded train
-"Highway to Hell" flickering fire on the right ramp
-Red Powdercoated Trim

Am I forgetting anything? For most, ACDC Prem was just such a better more complete experience, and you felt like you were definitely getting your money's worth for the cost difference.

I'm quite sure the magnet is never used to stop the bell. It will pulse to swing the bell (as though you hit it) if you hit your VIP pass during Hell's Bells.

LOTR and POTC were Stern's best sellers until AC/DC...but they were also in an era with more games on route. Way more AC/DC's went directly into homes vs. route...plus, keep in mind how many sold overseas - especially in Australia.