Mask fit is the single biggest reason people stop using CPAP, and it is almost entirely a matter of face shape, sleeping position, and luck. What is perfect for one person is unusable for the next, so this thread is not a "best mask" poll — it is a catalogue of situations. Useful things to say when you post: Which type — nasal cushion, nasal pillows, or full face — and the model. How you sleep — side, back, front, or all three in one night. Side sleepers and back sleepers rarely want the same mask. What went wrong with the ones that failed — top-of-nose pressure sore, leak into the eyes, whistling, straps loosening, the frame catching on the pillow. What fixed it — a different size in the same model counts, and is often the answer. Two notes worth repeating: A leaking mask is usually too tight, not too loose. Over-tightening deforms the cushion and breaks the seal it was shaped to make. Cushions are consumables. A cushion that has gone soft and shiny will leak no matter how well you fit it. Nothing on SomniTalk is medical advice. Talk to your own clinician before changing therapy.