We were there last Thursday night for a 7:30 ADR, we were not seated 8:00 (right when the fireworks started)-all that wait we could have watched them if they were a bit earlier.
Keep in mind the time of your seating in reference to park close. For evenings when the park closes later there's no problem. The characters came around to us twice which was nice, then someone came by and asked if we saw the characters which was great.
However I like to go to buffets in "waves". I like to get my salad stuff first and then go back up later for my dinner. By 8:20 they were already breaking down one side of the buffet. The food was refilled on the only side they had food on but I didn't expect that. It makes it more crowded if there's still a lot of diners left. There were also some items that were still low.
I have to admit I was a bit disappointed with dinner as we love lunch here and it's very similar with a few minor food changes. I didn't think it was worth $37 especially for my 12 yr old dd (and this wasn't holiday time or peak season). I would have much rather dined at Jiko or FF for that cost and eaten lunch here. If you're on the dining plan that's a different story.
We will return for lunch, but not dinner as I feel the food is fresher at lunch or EARLIER for the dinner buffet. I wouldn't do a late ADR again.