Finally, I'd like to point out that Itachi's stamina is not nearly as bad as people seem to think. His battle with Sasuke perfectly highlights this:
- He first had a sparring match with Kisame.
- Then had a genjutsu battle with Sasuke.
- Then used Tsukuyomi.
- Then had a Taijustu battle, before they exchanged several Jutsu.
- Then he used Amaterasu and covered an absolutely massive area with it. Easily hundreds of meters.
- He then activated Susano'o to survive Kirin.
- Then activated it again in order to seal away Hydra Orochimaru.
I genuinely don't understand how you can look at all that and say he has terrible stamina. Keep in mind that, again, he was dying from his illness and likely in great pain the whole time, he was suffering from the after effects of using the Mangekyo and was nearly blind, he was drained from firing off so many Jutsu that require a lot of chakra, and he was fatigued and injured from the battle. Obviously a healthy, fresh, Itachi won't have nearly as many disadvantages, so his stamina will hold up just fine.