Better chance of closing... Hernandez or Peralta?

Anyways... since Putz has been sacked as a closer and unfortunately I was not able to pick up Bell in his place I'm not stuck with David Hernandez and Joel Peralta on my roster as "potential" closers... now that Johnny CUeto is coming back from the DL, I gotta drop one of them... hence the question... which one do you think has a better shot at closing in the near future? We know that Heath Bell is a disaster waiting to happen every night but Arizona is always stubborn with their closers as evident in the Putz scenario... I feel like they will ride Heath Bell into oblivion... but the other scenario isn't much better either... Rodney even though he's struggling is probably a better overall option than Bell is and I think still has a much longer leash... who do you think I should keep?