In a word, YES!
I saw the Nuge is 2000 on the KISS tour, and he was unfuckingbelievable. He was loud, rude, crude, and SHREDDED IT. He closed with "The Great White Buffalo", which is reason enough to see him live.
As for ZZ, I haven't seen them, but my uncle has several times. He tells me that they do indeed put on a killer live show, and that Billy Gibbons is better live than on their albums.
See this show.