Kakuzu is good to use if you got someone who can give him loads of chakra (since he's a chakra monster), like, say, Itachi, Kisame, Sage Jiraiya. He also has very good SS damage if you level him up right. :loveliness:
I used to have him with my water main, along with GNW Ten-Ten and Gaara though... and it was terrible because almost all of their ss damage required at least 60 chakra (save for my main). -u-