Help ranking RPs

[futbol_no10_PSN]

Hi guys,
My pen needs another arm or 2. Right now I have Gagne, Rodney, Chapman, Goose and Eck that I trust, which leaves me two spots. Probably a lefty and a righty. How would you rank the following:

• Dibble

• McGee

• Britton

• Franco

• Nen

Also, I really like the Larry Walker card and think he can be near endgame OF, but would it be better to grab Signature Series Mo instead?

Thanks!