I went to Penn Law and I honestly do not see how it is humanly possible to do a JD/MBA there in three years. Maybe if they’re also doing summer sessions, but then you’re not getting work experience which puts you at a disadvantage vis-a-vis other law students.
I will tell you what I tell everyone else who asks about going to law school, and you should know that I loved law school and I enjoy being a lawyer. If you’re going to law school because you really want to be a lawyer, or because you will enjoy law school and have the means to go there and then plan on using the degree in various capacities, then go. But if you’re going to law school because you want a career that will make you a lot of money, then go to Business School instead. It’s a cheaper degree, a much easier degree overall (excluding the three days each term when your group projects are due), and there is a greater likelihood of making serious money.