This is a really tough one. For me Cream is the epoch of Clapton's abilities. He really shined brightly in those brief years and Bruce and Baker were excellent in their own right.
But Hendrix? Mitchell? Reading? So much freakin potential. All in all I think they had about the same number of really exceptional songs but even among these I'm always going for the Experience.
Very tough one but The Jimi Hendrix Experience has to get it.