My dad and I attended the 12/3 EMM. We got in line at the tapstyles around 7:00 (we hedged our bets and did use the Minnie Van, which was expensive at $37 ot including tip but worthwhile). We were the first at our respective tapstyles and even when taking our time and letting everyone else rush to SDMT, we still pretty much just walked right on. YMMV of course and it's not necessary to get there as early as we did unless you really want to do SDMT first. Otherwise I would go with the convention of saving it for last as the majority does tend to head to that one first.
I will add they did seem to put PPO's at separate tapstyles from the ones relegated to the EMM event (which will say "Event Entry" or something to that effect). However, I'm not sure if the two groups merged after they let us passed the tapstyles but not into Main Street.