I think Mayo could also run a lot of advanced tests. I dig into the PN research from time to time and a well-respected researcher, P James Dyck, is there. There are a number of doctors there that list only PN as their interest, not the long menu of other neurological conditions. The big strength of the Mayo Clinic is the collaboration between doctors that's ingrained in their culture.

That being said, having followed this board for a long time, I've seen people post negative experiences about the Arizona clinic, mixed reviews at the Florida one. I've been inclined to check out Rochester, where Dyck is based.