You do have to wait a while to get an appointment, but once you get in, their system is super streamlined, with all the tests already lined up for you. And I think they help keep demand low by being in such an out-of-the-way place. Only people who really NEED their services make the track to Rochester, MN. Anyone else goes to one of their easier to get to locations. (Which, I have heard, will soon include Paris and the UAE.)