This sound machine is great! I have used it every night since I got it and I am impressed with the quality of the machine as well as the sound and features it carries.I especially love the thunder,it sounds realistic. I also enjoy the fact that it has an AC adaptor or can use with batteries.I do sleep better,and am now able to sleep about 5 hours where before I would only sleep 3 hours a night so I also feel better by getting more sleep. [This review was collected as part of a promotion.]