I am of old-fartitude enough to have seen them on the Mother's Milk tour at the Apollo in Manchester, 1990.
Stood, kind of, and moshed, in front of Flea who was on fire. Actually, the whole band was.
And I saw them again this Wednesday at the O2, and I was sat way up high and sat back and watched and took in a great show, bar the technical hitches which actually gave way to lots of jamming, which I liked a lot but the crowd, which I had a great view of, would go flat. Give It Away was amazing with the heaviest ending I've heard for years, I think Flea was using his B*Assmaster. They're still one of my favourite bands.