I've been twice, and a friend of mine has been to almost everyone. I wouldn't depend on the guest too much since they really aren't the main focus of the show, really only 3-4 songs.
It's a ~90 min no intermission show, it's (almost) all his songs, with a really nice mix of his well known favorites, some unknown ones, stand-alone songs and he always premiers one new song from something he's just working on.
It's overall really fun. Seating is where it gets tricky and I would recommend calling Subculture and have them explain it to you because last time I honestly just tagged along with my friend and I can't describe it very precisely.
The sight lines in that space are pretty terrible so getting a good seat is important if you want to see faces. What they do is, they start handing out numbers some time in the afternoon. Then you come back I think one hour before the shoa and line up according to your number. You're let into the space in the order of your number and can then take whatever seat you want. A large portion of the front is usually reserved for his/the guest's guests, so the good seats really are limited.
So it's all pretty time intensive, esp considering Subculture is way out of the theater district. Just something to keep in mind for your trip planning.
