I have been using the Trilogy machine for 2 years now thanks to my sleep study doctor. She is not a pulmonologist but unlike my doctor and pulmonologist she was able to get the necessary test needed for the insurance to ok this Godsend of a machine. After the first night of using it I woke up refreshed, with energy and I actually dreamed. I hadn't done that in I don't know how long. I use a oxygenator with the machine. I am only 60 years old but was told that due to my condition I was now retired. Unfortunately my pulmonologist wants to remove me from this machine and put me on a bi-pap instead. He thinks I would do better with a non-invasive machine. I have no clue what non-invasive means. The only thing I can find is that this machine actually regulates itself to my breathing patterns whereas a bi-pap doesn't? Is this correct? If so, I have no idea why my doctor thinks this would be better and more beneficial for me.