Quoted from Caucasian2Step:Firepower:
Most people would say Firepower is about multiball. It's not. Firepower has no reason to start multiball other than it's a great gimmick. No PF multiplier, not jackpot to score... just great pin-theater and three balls whizzing around the PF. Firepower is about lighting the spinner and ripping it as hard as you can, as many times as you can. That's where your biggest scoring opportunity is. Simple and awesome!
While this is true, there is a key MB feature you are missing. Once you lock a ball, another pops into the shooter (provided you didn't save all three - when the lock is ready, I'll drain one if I have all three still going before locking).
This essentially gives you an extra ball. Continue with the MB, and once they both drain, plunge the new one for a freebie.
Since the extra ball in this game is one of the hardest in SS pinball to get, this allows for virtual extra balls.
As for the difference, I have never been a fan of BK, I'm not sure why. Classic game for sure, and FP doesn't seem like it has a lot, but has always felt like the base staple design of play for all future machines. I really believe without FP, big great DMD area machines would look much different.
I keep thinking that one day FP will be the next one on the list to go if I had to make a decision, but as my third purchase in the beginning , 25 machines later, while going through another 50 or so, with so many A listers, I still love coming around to it, and have no thoughts of selling.