RE: Alternative to Chin Strap
Bonjour is correct.
I just got the Mirage Liberty after my DME contact (he once had a sleep lab) warned me that I would not like it and that it was an "oldie". So far, I have to say he was right, but I haven't given up. Leaks and a too-small headgear are problems to solve, if upping moisture level relieves dry mouth. Overall, my ML is a hybrid experiment that continues with me changing masks back to the P10 after about one to two hours. Note: I don't like the heavy, stiff hose that joins the mask and comes with it. Further, the clips for the upper straps do look fragile; some say the elbow with the vent is fragile, too.
I wanted the similar Innomed Hybrid but my prominent nationwide supplier could-not/would-not supply it and it has the exclusive market under the Medicare competitive bidding area scheme (as I understood it). I wanted nasal pillows, as the P10 has, but wanted a way to simplify dealing with my mouth breathing--a problem well under control, but requiring two sealing devices, three with the cervical collar, for this side-sleeper. (Not to mention using an improvised anti-asphyxiation valve and Lansinoh, fourth and fifth elements.)
I tried FFM's, being a mouth breather who failed the tongue-seal approach: tried a ResMed F10 first for several months, then a Simplus (model?) briefly, and, last, an Amara View. The F10 was best performer re leaks and AHI, but I hated all the FFM's. I had hope but only occasional sealing success with the (most appealing but leaky) AV. And, yes, I repeatedly read and applied excellent mask-adjustment helps on the Board with some success on the various masks.
As others have pointed out, sealing the nare-pillow-contact contour/perimeter for pillows is much easier than sealing the more variable and much more lengthy sealing perimeter of any FFM. That made sense to me and challenged me to come up with a non-tape way to seal my mouth. I had tried three of Board-member recommended tapes.
I've been most pleased with the P10 (about one year with many nights of double naughts--no reported events and zero leaks ); this after improvising a mouth sealing method and taking Board advice to use a soft cervical collar rather than my three extended trials using purchased and improvised chin straps.
My guess is that I will resign myself to continued great success with the P10 and the complications of the Silipos sealing element, the elastic retainer that presses that sealing element to my face, the cervical collar, and the improvised anti-asphyxiation valve I use. Complicated, but not uncomfortable, and very effective. Somewhere on the Board I posted pictures that show the two pieces of the mouth sealer, the Silipos seal and its retainer. If you look, ignore the chin strap and FFM, both have been cast aside. I did steal the anti-asphyxiation valve elbow from the F10 to protect myself and, further, I now make a small slit in the Silipos seal where my upper and lower lip meet, again for safety. The seal and retainer keep my lips from flapping and leaking. The long-reuseable seal element has no adhesive, just a clinging, non-slip gel against the face.
Sorry about the long post, but for you, like so many struggling with leaks, chin straps and taping I wanted to share about my long journey from a high RDI, low-oxygen saturation state to a "double naught" state. Though weary of the complexity, I get great sleep and much better oxygen saturation. I should add that many find simple ways that are effective and simple to deal with such struggles as I have had. My way works for me (though I continue looking for a better way) and their way works for them--there are too many individual variables as bounjour pointed out.
2SB
I have no particular qualifications or expertise with respect to the apnea/cpap/sleep related content of my posts beyond my own user experiences and what I've learned from others on this site. Each of us bears the burden of evaluating the validity and applicability of what we read here before acting on it.
Of my 3 once-needed, helpful, and adjunctive devices I have listed, only the accelerometer remains operative (but now idle). My second CMS50I died, too, of old age and the so-so Dreem 2 needs head-positioning band repair--if, indeed, Dreem even supports use of it now.