I'm not sure there is any good or bad.
One particular moment that really made me question this was at the end of season 5, when the Man In Black accuses Jacob of bringing the ship to island. To me, he did not look evil. He looked annoyed and tired of playing the same old game. It gave me the impression that Jacob was the one using people and manipulating lives only to prove a point, while the Man In Black was disgusted by the whole affair.