i mostly use 3d studio max, and sometimes a lot of poser for animating and posing(so much easier to use than character studio). Making a person look real isnt really based on which particular program you are using as much on other factors thouh. Having a believable texture, a large amount of character study on how the human body works and looks, and good working knowledge of the program you are using and how best to apply it. Almost any of the programs discussed on this sight can make realistic looking people. Of course, a powerful renderer and a kick@$$ 3d card dont hurt either.