I think Oscar, if he is in the same shape he was against Flord or Mayorga could quite posibly box Margo to a UD.
Antonio struggles against guys his size or bigger ( Santos, Williams) so DLH at a similiar size would have that going for him. Margo also oreys on fighters that are weak minded (Cintron) and ODLH has been in enough big fights that there is no problem with that.
I say again if Oscar is in the same shape that he was v Mayorga he could beat Margarito.