Out of those 3 to choose from, Id definitely make sure Blackmon was one I played. Esp with PPR.
Those other 2 don't see the endzone they'll get you 6-12 pts but blackmon has a way higher ceiling with the same floor. I would put money on Blackmon scoring more than one of those RBs. As far as the RB to start, that's a toss up imo.
I actually have all 3 of those on my team as well.