I took my 4 year old daughter, and though it's a Broadway show, it's still supposed to be family friendly. I found it a bit long because of a lot of added songs that weren't in the movie- I would think most adults buying tickets without kids would understand if it were a bit shorter than the average 2.5hr show.
It was a bit long and in my opinion, not fully worth the $100/ticket. But should it come back in the $70-80 range I would definitely go for that. My daughter and I loved it, but I had more misgivings and negative thoughts than I've had in most shows.
We still had a great afternoon and saw a really lovely show. The singing was outstanding, Belle was just stunning.
It was just a bit too long, and a few too many extra songs.