I haven't seen this yet, but I just had dinner with a young woman (friend of my son) who works for a (the?) major costume shop in the city and their shows include this one. We were talking about it and I asked her where she thought was the best place to sit. She emphatically said "Front mezzanine" because apparently there is quite a bit that goes on there that people in parts of the orchestra can't see. So there's one opinion, anyway! 
Isherwood also discusses this a bit in his review from yesterday:
"Where to sit, you may wonder. I went to see the show twice in two days, first sitting on a banquette onstage and returning to sit in the orchestra.
For those who want to be closest to the action, the stage might be the place to be. For fans of Mr. Groban, perhaps the orchestra is the better choice. Then again, I had a friend who saw it from the mezzanine and felt he had an ideal view.
The answer really is, with a show this intoxicatingly good, there’s probably no such thing as a bum seat."
Maggie-the-schnoodle
Updated On: 11/15/16 at 12:29 PM