1 on 1 I think it would a good fight Itachi vs A, Bee vs Itachi, Sasuke vs A etc.. But 2 on 1 in my opinion, Itachi and Sasuke dont have the strength to beat the AB Combo. I say AB wins mid to high dif. I have alot of reasons why they they would.
Edit: EMS Sasuke OR Healthy Itachi vs both A and Bee in a 2 on 1 fight.