I was wondering about that, too. On another thread here Frank Abela wrote (October 5) "The motor upgrade improves the deck's pitch stability quite a bit. It's also meant to improve noise, although I haven't observed this myself to be honest (whereas I have noticed the pitch stability improvements). The motor upgrade is no joke - it really improves the deck substantially"
Thanks, Frank. I quoted you not because I doubt you, but because it is the only feedback we have had on this question, and I have no first-hand experience. One cannot audition a motor upgrade! My P3 with original motor and tonearm still beats CD any day. Your opinion counts, and I will consider this recommendation very seriously early next year.