This is an excellent pillow for a side sleeper. Really love it. Plan to travel with it. I don't like it as well with the CPAP mask as without. I feel like it still hits the mask a little bit in places to cause pressure. But it is much better than a regular pillow. But that is why 4 starts instead of 5. I haven't tried any other CPAP pillows yet, although I may eventually do so, just to see if I can find a better one. But this one I would still use, even if I found a better one. Probably take it to my parent's house and leave it there for visits.