First, let me tell you that I receive the Pureguardian 100 hour ultrasonic humidifier to tell my honest opinion. From the time I heard about a humidifier and its benefits, I wanted one, but just didn't get around purchasing one. So when I first open the package, I was so excited to try the product, but didn't know exactly what to expect or let alone install it. I would honestly say it took about 2 minutes to install, keep in mind you can input 1.5 gallons of water, which depending on how long you have the unit on could last about 3 days or more. I have been using this product for over 2 weeks, and I am really impressed about the benefits, no more stuffy or running nose, I can breathe easily and stay healthy during winter months. There is no need to replace or purchase any filters. This unit is really quiet, so you don't have to worry about the sound while you are sleeping or doing the things you like to do. I also like the night light option, what's great about it is that it isn't too bright, this is an option that kids would really like. There is a control panel where you can control the amount of mist, you can choose cool or warm. It keeps away mold and mildew, which is a plus. If you have little kids or just want to buy an humidifier for yourself I would definitely recommend you buy this unit, it's easy to use, quiet, it does what it says, and comes with a 3 year limited warranty.