I like some of his music, but the worst concert I ever attended was him performing in Pensacola in the late 80's.
Maybe 2,000 people there and you could sense he was just
trying to get it over with.
The worst concert i've ever been to (and i've been to scores) was the Moody Blues several years ago. A close second was ZZTop which was just too staged for my liking. I tried Ted Nugents show three times, really wanting to like it, but was always disappointed.
The best would of course include the numerous Pink Floyd shows i've seen and every single Skynyrd show i've been to.
The concert which i liked and wasn't expecting to like (i was dragged kicking and screaming) was The Who in San Jose several years ago. I never cared for their music but that concert was just terrific.
I got free tickets to one of his concerts in the early 90's. It was the worst excuse for a concert that I have ever been to (and I've been to some bad concerts). He came on stage obviously drunk or stoned. He slurred his words and was wobbling around so much he could barely stand up. He forgot the words to some of his most famous songs and his voice was just totally gone. He attempted to sing about 5 or 6 songs and then just walked off the stage. It was pitiful.