Dr. Park gave a presentation at our SA meeting some two years ago. I also read his recent book (forget the title) and attended some of his online meetings. All were excellent. It was clear to me that Dr. Park is a real scientist.
I saw Dr. Park who had a short list of dentists who deal with sleep issues. Since Dr. Barry Chase accepts insurance, I elected to see him. Note, however: Not everyone is a candidate for MAD. I was and am. Dr. Park could tell by checking the architecture of my upper palate and mouth.
I happen to be one of those strange people who actually likes her APAP (which Dr. Park suggested I try; I had been using a CPAP) and I also like the mandibular advancement device (MAD).
Dr. Park suggested that I try sleeping with both. I have done that a few times. Last night, after having my MAD advanced just a bit on Monday, I slept with both and had a really, really good night of sleep. I don't know if I was "due" a good night of sleep or what the reason is, but I relished it.