I recently had a "sleep study" done. Actually it was my second study. It had already been determined that I had moderate sleep apnea and needed to have have one of those dreadful masks fitted to my head. The only question was which mask and what pressure.
Without boring you overmuch with the details of my sleep habits, I usually am asleep a few minutes after my head hits the pillow, although I do sometimes wake up in the night. With the dreadful mask it took me four hours and two sleeping pills to get to sleep, although I did sleep soundly for four hours. But sleeping with a mask clearly isn't going to be easy.
I actually preferred the mask that covered my whole face rather than only my nose. The nose mask hurt my lip. Of course I could just lose 25 pounds and tell them to keep their breathing machines. But wearing the mask is apparently easier than losing the weight.