My husband just recently got his. When he went in for his followup appointment, a rep from the medical equipment company happened to be in the building. He was having a few problems with the mask fitting correctly, so they fitted him with another one, a different type, sort of a gel thing. As it turned out, that happened to be the last day he could have exchanged it. This mask works a lot better for him. So just be sure to keep any follow-up appointments, and if your equipment doesn't work quite right, be sure to tell them. My husband no longer snores (a huge blessing for me!) and even though he was having absolutely no problems sleeping before, he says he has more energy later in the evening. He also went from 60-80 episodes a night to a half an episode per night (15 over a 30 day span). Evidently the machine keeps track and it must wirelessly transmit the information. Which I find just a little offputting!