I absolutely love the Madison Blues set, and I play it a lot. There are 5 'live in the studio' tracks:
Crazy About You
Down At The Crown
Tell Me All The Things You Do
Station Man
Purple Dancer
The first two are unavailable officially anywhere else as studio tracks, as far as I know, and they're both fantastic. I think they're from November 1970 and they're the first recordings with Chris officially a Mac member (I think). There was another recording of Down At The Crown from those sessions, and they also did Sandy Mary and Turn Me Loose - I don't think they've surfaced anywhere yet, unless someone else knows about it
The Kiln House tour live stuff is mostly excellent, although there were sound problems here and there - nothing too bad though. Lots more songs unavailable (officially at least) elsewhere. You also get 4 Christine Perfect songs (all good) and the Jeremy interview from 19 Feb 2002. Well worth the price in my humble opinion