We were there in April and watched it 3 times, from 3 different places. 1st from Tomorrowland bridge, we thought this was the best place at the time, great view and hardly anyone around. The next time we watched it from the Plaza restaurant Terrace. We also staked out a spot early and grabbed something to eat for dinner while we waited. It quickly got crowded when it got near show time. It was a wonderful view, and we got to sit down! HOWEVER, the 3rd time we watched it from Main St. There are fireworks on both sides of the castle and effects shown on the castle and you just do not get the full effect unless you watch the fireworks from Main Street. That way you see them from both sides of the castle. It is an awesome show. And we didn't realize just how awesome until we saw the full effect from Main Street. The Train Station is suppose to be a great place to view from, and we saw people sitting there.
It's neat from anywhere, but if you are only going to see it once, try to see it from Main St. IMO.
Lori