Both are fantastic synthesizers, but I think the Summit sounds a bit clearer and warmer and, with the 3 digital Oxford oscillators per voice, simply has more possibilities pro forma, is 16-voice and very easy to edit. The Polybrute, on the other hand, has the mega-genius morph function, can sound wonderfully croaky and breathy, but only has 6 voices etc. I'm glad to have both, but if in doubt, I would prefer the Summit.
