This one unit covered my lower level with no problems. I never even had to refill the tanks during my two-week test, and the air quality improved in my home as well.
I'm sold on having more connected appliances, and this one is a solid performer. You can easily adjust the humidity level whether you are even at home or not. My only slight gripe is the price. I've seen humidifiers on sale at Home Depot for as low as $90 that claim to cover an entire home. For $200, you would want to be fairly attracted to the entertainment value of adjusting humidity levels.
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