I find bp's boring (again my own opinion). They don't move too much, they're common as dirt and well, I'm a colubrid person.
I say mex black. They get to a decent size, don't musk once they're tamed, not too expensive which leaves you money to get a lot of cool supplies. Plus the really black ones are just stunningly gorgeous, black and irridescent, ooooooo....
I find that not a lot of BRB's live up to my expectations of a RED and shiny snake. Even those tooted as RED, just aren't.