I bailed out on 7SD a while ago. It just got so bad. They get a "B" for being nice guys, but an "F" for effort. I can't bring myself to even try to listen to these other piles of crap.
I think 7SD has gotten really good since they went to the live variety show format. The real truth, though, like someone else said, is that they're at the best when there's no topic. Andy Breckman is a very funny guy and I just enjoy hearing him talk.
See, I kinda hate those. Not only are they completely removed from the show's premise (stunt radio, fatal flaw, blah blah blah), Ken and Andy (who I agree is a very funny guy and the reason to listen) get far less time on mic for those shows. It's lose-lose for me. But I could just be bitter because I don't care for most of their guests.
I basically agree with you about the guests, especially the musical guests. I enjoy hearing Andy interviewing the folks and struggling with his twin impulses to be his usual rude, wise-cracking self and to be nice to the person who has agreed to help the show (and who is sitting right next to him). I do think he's funny while interviewing the guests, too.
As far as being removed from the show's premise, fair enough. I can't really argue with that point, although I've only been listening for about a year so maybe I'm not as attached to the stunt radio angle as other long-time listeners.