Pretty sure Aerosmith has that same combo rule, i.e. doubles the score of the next shot (this is why shots flash rapidly)
Quoted from Caucasian2Step:Better code goes to kiss. Aerosmith has some bugs in the modes that need to be squashed. Serious exploits. The one thing the kids has going for it it makes such a huge difference is the combo rule set. Doubling the score on your shot at any time during the game means that a big jackpot whether it's in the star child arch or somewhere down Gene's neck can be doubled by hitting a ramp first and then making A skillful shot on the fly to double a super jackpot shot. It's the simplest of real designs it makes such a huge difference on this game. Playfield multipliers for completing modes within a single ball of play means that long term skillful defense and accurate shots will give you a huge score. That is the essence of the rules Awarding great scores for great play.
Code / rules, kiss is the winner.
Both games are Jon Borg designs and they have their own interesting lock mechanisms. I'm not a big fan of the four or three bumpers on the lower left-hand side of the game on Aerosmith, it's a killer, I've seen the ball hit a pop bumper and go straight out the left outline. With a bit of consistency.
Other than that, grandpa rock is where it's at!