I saw Amy during her "Stag" tour, and liked it! She has a different approach to her music by herself than with Amy, and as a long time fan of the Girls, it took me a while to get over that. Once I embraced the raw nature of Amy's individual style, I got into the groove. As for a not-so-good show, that happens to EVERY musician at some time or another.
Last summer the Girls played the zoo here in Portland and I couldn't go, which REALLY bummed me out because I wanted to take my kids to see them for the first time! I've seen then a dozen times and wasn't going to go unless we all could. After the show, a friend of mine who went told me she was really dissapointed. She said they were very low in energy and maybe even sick. I have never seen a show from them I didn't love(unless you count the 4 songs they played on the Lilithe tour:) It goes to show you that the best musicians can have a bad day together, as well as apart!