The pros and cons of the good samaritan rule versus the American bystander rule?

Under the Good Samaritan Rule (which is not valid in all states), someone could not be sued or prosecuted if, in good faith, they voluntarily rendered and/or summoned aid for an imperiled stranger.

Under the American Bystander Rule a person would have to have the legal duty to act or aid, and be required to do so, if they are employed in some "helpijng occupation," or if they have some other legal obligation which requires them to act (e.g.: a special, or familial, relationship with person in distress).

The two are clearly different and the reader can draw their own conclusion about the pros and cons of one versus the other.