In the winter months the air in my house dries out and it's terrible especially when one of us catches a cold. I have heard negative things about warm mist humidifiers and have always used cool mist. But when I checked into the variety of humidifiers I ran across a Vicks Warm Mist that kills 99% of germs while it is in use. I'm glad I bought the Vicks V790 Warm Moisture Humidifier because it has made breathing while sick much easier. My daughter has breathing issues and this humidifier has helped her tremendously. It has dual water containers and I am able to adjust the level of humidity in the room. When one of us is sick I will add Vicks Vaposteam to the water and it's like adding menthol to the air and opens the nose and lungs up to make breathing easier. I also have found that this humidifier will warm a room up with the warm mist. I wouldn't use just any warm mist humidifier but this one has a guarantee that it's giving off a germ free mist. This machine has a low sound to it and will run a whole day before it needs to be refilled. Now I won't use it much during the summer months and the only downside is cleaning it, our water is hard and it's very hard to clean. I've learned that if I use distilled water it's not as hard to clean. This truly has been a life saver in my household in adding the moisture we need in the winter months and around flu and cold season.