I have had this unit in one of my houses since this past winter, and it is by far the best humidifier I own. It is quiet enough to keep in the bedroom at night, but powerful enough to easily humidify the 1000 square feet comfortably. With adjustable humidity settings, and 2 large tanks that you can fill separately without shutting the unit off make this very easy to use. The only thing that keeps me from 5 stars is it is difficult at time for me to get the filters due to my rural location, and the price is between 12-20 dollars depending on where I get them. Molding can be minimized with the treatment tablets (protec tank tabs) that are available, or the tiny amount of ammonia another person mentioned (if you don't mind the mild ammonia odor). I have owned 5 different brands from lasko, holmes, honeywell, hunter, and Essick, and this is the best of them all. Overall, a very good value for the extra price.