Board Thread:Versus Debates/@comment-26005711-20150530210611/@comment-26127155-20150609125508

Team Uchiha
 * Itachi's Totsuka blade would be able to permanently end any of the Sannin.
 * Kotoamatsukami would instantly wreck the Sannin ( Itachi's crow has this jutsu), it is basically super hax.
 * Team Uchiha have at least two top tier genjutsu users (not sure about Izuna) and this combination would be deadly.
 * Obito can avoid basically any attack and he could use Kamui to separate the sannin from each other.

Team Sannin
 * Manda, Gamabunta, Katsuyu and other summons are the sannins's best bet for winning this fight.
 * Edo tensei could always be a last resort (requires sacrifice).
 * Tsunade could be a healer.
 * Jiraiya's sage mode is powerful.

Obito has been shown to trap creatures of Manda's size in a genjutsu and Manda himself was caught in Sasuke's genjutsu (Itachi could presumably accomplish this feat as well). Itachi has absolutely humiliated Orochimaru in every circumstance they meet, and this would quickly create a 3v2 situation (with Kotoamatsukami 3V1) where the remaining Sannin would be overpowered by the Uchiha.