The simplistic nature of the multiple choice questions also leaves out a great many schools of economic thought, although I thoroughly enjoyed their take on Chicago-style empiricism.
I tend to favor a blend of Austrian-style and Chicago-style economics, but neither school really suits me philosophically. Alas, I agree with Objectivist economics, which holds philosophic premises similar to the axioms of the Austrian school, but concludes the necessity of government involvement in things like national defense and criminal justice, whereas Austrian theory tends to favor anarcho-capatalism.
However, I think its important to note that the Mises Institute, in true Austrian tradition, does not hold a monopoly on Austrian economic theory. Ludwig von Mises himself had nothing to do with the institute. Their interpretations are not necessarily gospel among all who consider themselves economists of the Austrian tradition.
Also, frankly, I despise Lew Rockwell and Murray Rothbard and the whole "paleo-libertarian" sect. They've successfully associated free market economics with bigotry and irrational moral premises.
I got a 94/100 btw, with three "Chicago" answers and the rest Austrian, but truthfully, the answers I wanted to provide were rarely available.