I would go with Kakashi & Kakuzu because of recent chapters. It is shown that Hashirama was no fodder and Kakuzu fought him and obviously survived which means Kakuzu is no pushover.
Kisame only has Water Release which is no match for Kakuzu's earth style monster.
Kakashi is obviously more powerful than Gai and if he can connect an effective Kamui it's over but it's highly unlikely because of Gai's speed & gates.
I'm really confused. I don't know which team is stronger :confused: