kinda depends on A's attitude from the get-go, the information he has on them, and the place kind of matters too. if A starts off going all out like with sasuke he will probably win, but if he trys to just toy with them chances are he will get caught by some kind of trap (puppet masters are good at setting traps and are pretty intelligent) and as we all know, even a little poison inhaled of injected and he is paralyzed in seconds, and if he doesnt knw of sasori's heart, he is kind of a block head, itd be a long lasting fight and raises his chances of being poisoned, finally, if they are in an enclosed space rather than an open field or something, then obviously sasori's team has more of an advantage (he doesnt have as much room to run around), unless he like blows out the cieling and walls xD...but its a tough call