All the talk recentely (eternally?) about BBb vs CC etc makes me think about pieces written with a specific pitch of tuba in mind.
Malcolm Arnold "Fantasy for Tuba"....definitely an Eb piece in my mind. Same with the Gregson, though less definitively. Not that either won't work on other key tubas, but the fingers do fall much easier. In the Fantasy, f'rinstance, the 16th note licks finger much more smoothly on Eb. I've done it on BBb and F, and this is the easiest way I've encountered.
Any others?
And, speaking of Gregson, the quote from the VW is famous, but what about the Gordon Jacob reference right after it? I've never heard that mentioned.