Brett Favre is available in my fantasy league, should I pick him up?

Is it too much of a gamble? Will he even have a season that is good enough to have him on my team? Also Beanie Wells is available, Montario Hardesty, Joseph Addai, Cedric Benson, and Ryan Grant are my RB's. Should i pick up Wells or wont he be much of a factor in AZ? Thanks for answering!