Just an FYI and maybe a personal bias! I went to Duke University for the valves. I did weeks of research on them only to find that Duke had gotten in on the ground floor so to speak of the mega-analysis of the valves. There are 2 different kinds, both basically do the same thing just different companies. That "ground floor" was about 16 years ago so they have been doing them for a long time. The important thing is to know where the Pulmonologist trained and how long have they been inserting them. The other important thing. You need to go where you feel the most comfortable. I wish you the best of luck and hope that you will have the same great results that I have had.