Here's how I see it (so it is subjective).
SM advantages over ST Pro: Doc Ock magnet and VUK, moving Doc Ock.
ST Pro advantages over SM: looping upper flipper shot, saucer shot on lower left, color-changing inserts.
I don't see how anyone could say "not even close". I like the single drop target over the motorized 3-bank, but it's about a wash for me.
It all comes down to CODE, gentlemen. So, it's too soon to tell which is the better game.