I've always been intrigued by that program but was intimidated by the fact that they only accept 2 or 3 people, mostly from their own law school (though I could be wrong about that, I'm just deducing from their site).
This is a common and unfortunate misunderstanding about the JSP program. In recent years, the program has admitted relatively large (10-14) numbers of students, and very few of them come from the law school. Some come in with law degrees, some pursue law degrees concurrently, and others never pursue a JD at all.