Most of us replying to this topic do know the Sarplaninac and the good and the bad with the breed and we also know that the breed does not define the dog. What we do not know is the capability of the prospective owner so to properly answer an question like this we must first know about the person asking the question.  I will not start from a position that there is something wrong with the breed.  The only thing wrong with most breeds is the stupidity of the owners. 

Not implying that you fit that category - but lets first assume that the dogs are what they are.. canine specimen and they do have variations .. the only thing we can't predict is the owner.