I think the outcome is good and bad. I actually was not bothered by the mask itself (nasal pillows) at all (well some, but nothing to mention). In the beginning it took some time to get accustomed with the pressure when breathing out, but I think I got a hang of that. Noises didn't bother me either.
I went to bed early to get myself accustomed with the setup before even trying to get sleep. but after hour or so laying flat I started to feel like the sleep is moving in. But then the problems started. When I am just about to doze off, air gets into my mouth and my cheeks get blown out and finally the air is released between the lips. Naturally this cancels the dozing off and I need to start from the beginning.
I think this was also the main reason why I kept on waking up several times after finally falling in to some deeper sleep. Especially when the pressure went up my mouth would open. This is at least my interpretation - difficult to say for sure because of the half-sleep state in which I spent quite a long times during the night.
I didn't know much about the physiology of my mouth before, but I figured out I could block the airflow to my mouth using two different methods. One is to use my tongue as a hatch by keeping it pushed against the top of my mouth. This seemed to be the natural way to do it for me, but seemed like my tongue would relax when falling asleep and the air would break lose.
The other way to accomplish the blockade is to do it in the back of my mouth. This didn't come naturally at first, but I figured it out during the course of the night. It seemed like this worked better.
Any comments about this issue with opening my mouth? I don't think a chin strap would do any difference because my chin hardly moves. My lips would just open marginally and the air starts to escape through there. Will I learn to keep my mouth shut? Or learn not to wake up even this happens? I would not like to consider the full face mask because the nasal pillow version feels rather comfy.
And, how an earth do you yawn with this thing without choking?
Anyway, I still have two nights to try it out and on Friday morning I will head back to the sleep clinic to discuss about my experiences.