Kisame. Samehada may be useless against Guy's attacks, but it can still defend kisame, leech of guy's chakra, and heal kisame. and merge with kisame in that water pool, giving him a speed and durability boost.
vs Guy, Kisame was without samehada and already somewhat weakened by Naruto. yet if Gai didn't have backup, Kisame would have outlasted him when the gate effect kicks in, guy was even more helpless than a kitten by the time yamato and co arrived. yet he still had enough strength to break through yamato's wood blocks and cast another powerful jutsu. Gai is great, but Kisame is on a different level
vs Guy, Kisame was without samehada and already somewhat weakened by Naruto. yet if Gai didn't have backup, Kisame would have outlasted him when the gate effect kicks in, guy was even more helpless than a kitten by the time yamato and co arrived. yet he still had enough strength to break through yamato's wood blocks and cast another powerful jutsu. Gai is great, but Kisame is on a different level