I honestly can't call it. I'll tell you one thing though-- the winner of that fight is the undisputed best HW in the world. Two deserving, experienced, well rounded fighters going at it. No fucking WWE slobs who have fought hand picked opponents and had the belt after 3 fights.
My early gut-- Im going with Velasquez. That ASU wrestling dominated camp of Velasquez and Bader is going to be on top for a long time imo.