Id take Davis over Barrera, but the greatest mexican of all time Marquez would knock davis out at 130
Does Barrera really need to do much to keep Davis "off him" though? Sure he comes forward at times but he's not a cut off the ring and impose his will kind of fighter. Also as we've seen thus far it doesn't take massive shots to deter him. The weight might be a bit iffy bout MAB would be the best and most intelligent boxer he's faced by miles.
If Barrera can go the distance with Pac at 130, and box with Marquez, I think he has it in him to beat Tank.