#1 Whirlwind - I'm a sucker for Lawlor games anyway, but to me this may be the best designed pin of all time. Every shot feels satisfying and the multiball relies heavily on patience and control. Pure fun, intense pinball IMO.
#2 BSD - Probably my favorite DMD game. Really rewards accurate and consistent shot making (and punishes missed shots). The theme is immersive and the callouts are great with some of the best mechs (mist) and features in pinball. The prospect of trying to set up a game better than the one before keeps the replay-ability high, not to mention the ramps just feel awesome.
#3 Taxi - Obviously I love the system 11 era. Classic layout, multiple ways to approach the game with some amazing multiball music. When you get in the groove on the ramps it feels great. Makes you much better at post transfers and dead bouncing in order to effectively play the game.