my list why batman would best superma....er I mean p4p
1) Anderson Silva
4) BJ Penn (a true example of the meaning P4P)
6) JBJ (a bit early, but plenty of potential
8) Frankie Edgar
9) Jose Aldo (also a bit early)
10) Lyoto Machida
Also I know the term P4P gets argued like there is no tomorrow, but the true meaning of pound 4 pound is "all things considered equal". In other words if lets say if Aldo fought Cain and they would be of close weight and size, from their skills alone who would win? Being p4p means you would be able to compete and maybe dominate in any division by skill alone if other measures such as height and weight did not apply.