Quoted from Whysnow:high keepability = MM
I my opinion, keepability usually goes hand in hand with the things that make a pin popular to begin with:FunFunny and timeless themeChallenging for a playerEasy enough to put a smile on a non-players faceBall times are usually pretty short but can also have bust out games that last 30minMany tasks to complete or shoot for (i.e. just blow up castles, load all madness before going to merlin, high score, defeat KOP, etc...)
MM for sure is a keeper.
So much so,I have two.
One being restored,one to play while I wait for the other