It's sort of a moving target because they keep changing the process (I did it twice for PTN and once with MSEP). I thought it was decent, though they bumped up the price since the last time.
We did the MSEP Aladdin's Oasis on Monday 6/12 for the 8:45 PM show (this is the first of 2 shows). The viewing area is located across from It's a Small World.
If you look at the picture above (taken after the viewing area was closed about 10 minutes before the parade), I am standing close to the corner of the area (it's a little bit behind me). You can sort of see down the center of the picture that rope way down in the distance is where the area starts. It goes behind me, wraps around the corner and goes over to the left of me. It does not include the street level, so the railing you see on the right is the front of the viewing area. There are some steps on the left and you can see a higher level that is also included in the viewing area. The parade starts behind me and to the left, wraps around the corner, and continues away from me down the street on the right side. I chose to stand at the railing, while my parents sat on that ledge you see over on the left. Since it was relatively empty, I just sat on the floor while we were waiting for the parade and stood when it started.
View of the parade from the railing is excellent. Since it is elevated, there is no one blocking your view, and I actually prefer the railing over sitting on the curb. My camera was resting on the top of the railing when I took this picture, so my actual vantage point is a bit higher. You can see the heads of the people sitting on the curb at the bottom of the picture.
The tickets you get state that the viewing area closes at 8:30 PM for the 8:45 PM show. We arrived around 7:45 PM. The viewing area was open (which was different than previous times where we had to line up) and there were only a handful of people, so we pretty much had our pick of where we wanted to stand. This picture was taken after the area was closed (around 8:30), so you can see there was plenty of room. You could have come in right at 8:30 and had a decent view of the parade, though maybe not at the front railing.
That being said, the following day we ate at Carnation cafe. As we were leaving the Cafe around 7:30PM, there was still space on main street that you probably could have taken (not on the curb though). Personally though I liked having the security of knowing I have a spot in the viewing area.
The fireworks projections play on IASW afterwards, but we did not stay for the fireworks so can't comment on how good the fireworks are from there.
Hope this helps!