Kelmac, at the sleep study center, I used a mask called the Quattro. Image
here. I fell asleep ok, but by the 5th-6th hour of the study, the sensor they clip to your finger to monitor your Oxygen levels felt like it was being squeezed in a vice grip. It was way too tight. That night was not a good night of sleep.
I had heard good things about the nasal pillows on here, so I suggested maybe I try that one. The one I have is called the Opus. Image
here.
The girl who gave me my CPAP orientation suggested I wait a week or so before I switch masks. I have also been given Flonase spray to open the nasal passages, which has helped.