I don't believe that he's weak. He's a jinchuuriki and seems to be on a high level, possibly around Kage. And he appears to be smart. I can't say for sure though, but in the fight against Taka he seemed to overpower them for awhile and lasted an awfully long time against an Uchiha, a healer, a swordsman, and a very strong madman. And he managed to get away when it got to be too much. So no, I wouldn't say he's weak. He's actually very strong but he's not the strongest(or very close to it) character.