As far as singers go, I went to see Vivian Green and Musiq in Detroit this past week. Vivian sang her heart out for an hour and Musiq seriously rocked it for 90 minutes. I was definitely satisfied when I left, but I could have stayed for more from both of them. So I think 90 min to 2 hours is really good. Those Germans must be hard to please, they should be glad to get what they got.