Hi,
Frank Zappa DOES deserve to be mentioned, although he is a rather hard taste to get into. The music itself, in just about in any album is amazing and very well composed and defined. Over the years, this stuff has gotten "better", though not many folks have the diversity, talent or desire, to play more of his stuff. He also has a lot of classical music and untitled stuff still in the vaults that the trust has no idea how to show it or release it. Their warm ups and sound checks were usually way better than most concerts, and were always recorded.