You always tend to surprise me. As we've learned, Deidara is terrible against sharingan users. Here we have Orochimaru with all of Sasuke's skills (3-Tomoe Sharingan) and you don't think he can beat Deidara? Also, Deidara is restricted from using his two most powerful techniques that actually gave Sasuke a hard time! OroItachi or OroSasuke owns Deidara, while the other two bodies beat him with some difficulty. As for Sasori, I don't even think his poison would kill Orochimaru, as he is such a genetic freak.
WTF are you talking about?
How is Deidara going to be looking into the uchiha fcuks eyes when he's bombing them while Sasori is spamming his poison needles? Maybe with Itachi, it'll be too much for the two but there are other Akatsuki to finish the job.
-Tentacle rape guy that can spam Katons, Futons and Sutons plus he has nearly unbreakable armor.
-paper girl......ok, she's phail
-a guy that can spam summons, made up of six bodies, can revive these said bodies from death, can absorb ninjutsu, make it rain, has rockett arms and a sword that can disrupt chakra.
-a unkillable man that bettered Kakashi in hand2hand combat and practically one cut from him means instana death.
-a puppet master that can summon over 100 poison puppets, fire poison gas/needles and summon the Kazekage puppet that has iron sand.
-a girly man that can spam bombs across the landscape and create citybusters while flying.
As for Oro being immune to poison.....lol.
EDIT: Sasori and Deidara tank