Lets cut the bullshit, shall we. Sasuke was absolutely dead serious about this fight. He needed to complete Tobi's mission for them to be independent of Akatsuki. Bee never took it seriously which is true when he used the tentacle trick to ditch the fight. He was intially trying to test his abilities through his other teammates but after Bee wrecked Suigetsu and Jugo first time, Sasuke joined him for the Kenjutsu battle, which he lost badly.
OT: Bee honestly would have won that fight. I can't see Sasuke winning at all. If Bee decoded to finish Sasuke he probably could've. Why?
Simple because Sasuke was so exhausted from using Amaterasu and after pulling off the trick he could use Lariato on Sasuke's neck and chop him off. People complain nerf this nerf that, first of all he has no more CM abilities bar Kirin vecause Itachi sucked the 8 headed serpent with his Totsuka Blade. OP give some credit to Sasuke, he did dodge a full mastered Jinchuriki's Lariato and temporarily subdued him with Genjutsu.
Overall rating wise it was 7:3 in Killer B's favor.