You wont get much for betting on just a straight win for Floyd so you might as well go with the underdog or bet on something else like Knockdowns.
I think it's going to be an interesting fight and I think Floyd is more nervous as he's got more to lose.
I put a bet on Manny to be knocked down at some point during the fight. Pretty good odds at an enhanced special of 5/1. I think he will get knocked down at one point but I could see the fight going all the way or Floyd winning by KO in the later stages.