Just to add on to above. It took me 2 years to get truly used to sleeping in my full face mask (it's ratcheted on my face due to max pressures needed because I'm just fucked I guess). THAT SAID, even just a couple hours a night made a huge difference in bloods, function and all quantitative and qualitative measures. Just keep grinding at it. Don't let the "perfect" be the enemy of sufficient to improve. This thing matters and a lot of us here have them and only a lucky few had it go smooth and easy at the onset. Keep at it!