RE: Desperate to resolve Mask Farts (New User with serious neurological complications))
I have an F40. I love it, but it farts at pressure 14. At 13, no leaks. I like it, because it's light. Very comfortable. If I could, I'd use a nasal mask, but I'm not a candidate for unrelated reasons.
FWIW don't use a nasal mask unless your nostrils both work fine. Some folks have a deviated septum and other internal nose obstructions.
On a FFM, the lower corners need to be wider than your smile.
RE: Desperate to resolve Mask Farts (New User with serious neurological complications))
I have used FFMs for 16 years. Six models including Resmed F10/F20 and other brands were plagued with leaks no matter how tight the straps or how I adjusted them. Four months ago I bought a Fisher Paykel Evora Full. It is described as a hybrid full face mask. It took me 3 months to adapt to it. For over a month now I have not gotten a Red Frowny (bad leak night) on my ResMed AirSense 10 and OSCAR reports show few leaks.
I move quite a bit during sleep rolling from side to side and to my back each night. Unlike previous conventional full face masks, the Evora Full's seal is not compromised by the movement nearly as much. Another surprising thing is for the first time in 16 years I am waking without a severely dry mouth. I suspect the mask is causing me to not mouth breathe as much.
The next ones I want to try are a ResMed F30 and F30i.
Finding a mask that works best is frustrating and expensive. The Evora Full may be my best one but others may be even better. I am very glad the hybrid masks are now available.
I only give suggestions from experience as a fellow CPAP user, not professional advice.