Lots of great and varied replies. So, how much of this will you remember at the doc's office? Me, I'd print this page out to use as one of my 'last shots' if for any reason the conversation isn't going well. I do agree that it's in the Doc's own best interests to give you what you ask for, again, no harm to him/her - but the potential if he says 'no' could be not so good...
*I* am not a DOCTOR or any type of Health Care Professional. My thoughts/suggestions/ideas are strictly only my opinions.
"Only two defining forces have ever offered to die for you. Jesus Christ and the American Soldier. One died for your Soul, the other for your Freedom."
My prescription doesn't say an exact machine/model -- just the pressure settings (settings imply APAP) / humidifier / masks for life.
However, I specifically requested an S9 AutoSet from the supplier that the doc recommended I use (a local outfit) and the supplier delivered the AutoSet.
The Doctor signed the RX for S9 Auto-Set and on the same day I went to the new DME and received the AutoSet. And I'm looking at sleep data this morning. The new DME made all the difference in the world. The first DME they hooked me up with wanted me to pay them $325 cash extra for an Auto Set.
BTW, the Resmed Airfit P10 mask works great.
Sounds like you are off to a good start, a new, (more cooperative,) DME, a mask you like, and a new S9Autoset.