I saw them on Saturday night before last (the 15th) at Festival Hall. The stage was slightly too low to make it easy for most of us to see them. It was fairly crowded. If you wanted to you could complain that the sound system isn’t perfect as well.
The main act had to be stopped as someone collapsed in the audience and needed to be stretchered out.
This didn’t matter as Wolfmother are fantastic. I have never seen anything as well done.