Man I am tired today, around midnight my nose clogged up and woke me up and I had to take the mask off, man it was terrible trying to sleep without it. I had the worst time with my breathing, and I am so tired today! I can't see how your hubby doesn't feel tired after not using the machine, I definitely feel it after three good hours of sleep to 6 more without it, my throat was like paper and my tongue all yucky, I won't miss using it again if my nose lets me. Best wishes to you and your husband BMW.