I think the "Who is better" question is a silly question, but it's going to be ask so here is my .02.
Take Bran and put him in Tool, can he comprehend the polyrhythmic stuff? Can he use effects like Danny? Is he capable of playing is four or five different types of bands, and not just making it sound convincing, but actually understanding all of it.
I'm pretty sure from what I've seen personally from Danny, that he's just as fast as anyone else. Not to mention the fact that once you reach the level of Danny, speed is just a small workout a day!
I respect Brann as well, and I'm not bashing him, who knows maybe he can hang with Dennis Chambers and Steve Smith like I think Danny can. But musically, I think Danny brings more to the table.