My health has improved greatly since using one. I have 15lbs pressure and the cost and style differ according to your needs. As I am a mouth breather, I have to wear a full mask and use a humidifier as well. I can't go to sleep without it. Before I purchased it, I was rarely getting more than 2 hours of sleep every night and was very sick with related illnesses. Now the other illnesses are under control and the lag time for me to get to sleep is only about 10 minutes.I have more energy and lost 15 kilos in weight without doing anything else except use the CPAP machine. So you see, I am an ambassador for the machine, whilst I was a skeptic beforehand.