I've had a CPAP machine for about five years. Actually I have two - a small Medtronic model for travel and another for my bedside. I like the Medtronic best. I have two types of mask. I have a mask that covers my nose but not my mouth. I like it best. I also have a nasal pillow. Don't like it at all. Recently I got a full face mask when I purchased a new mask, but did not like it either so they took it back. My first CPAP has a moisture attachment but I have disconnected it. Don't need more humidity in NC.
If you have not tried several styles of masks, you should. I love mine. When I put it on, I think my brain is conditioned to relax. Without it, I toss and turn for hours. I also take Ambien at night.
There are places on the Internet that sell reconditioned CPAP machines for a fraction of the cost of a new one (my last was just$165), and they will give you the codes to set the pressure to match your prescription. Both of my machines have altitude adjustments. I live at sea level. On a recent trip to Breckenridge CO, I spent a few nights at about 12K feet. I couldn't seem to inhale enough air when I relaxed. I remembered the adjustment and corrected the machine to the highest altitude setting. Worked like a charm.