I also have seen a lot of very good acts, but I recently saw David Bowie, and to put it mildly he was absolutely awe-inspiring. I was never a huge fan, in that I quite liked his music but very much not a devotee. My wife, who had very little experience of him at all, was also blown away. Technically he was superb, had great stage presence, played a good mix of classics and new stuff, which was excellent even at first listen, and clearly enjoyed himself immensely. The best by a long way!!