You can smell the freshness in the air! We use it at night during the cold months and I wake up with less dry eyes, nose, and skin. We choose this one because it is evaporative and it cleans itself by drying out the air filter thoroughly when the water is gone. If you did want to clean it, it wouldn't be difficult to run vinegar through it.
                    The only cons are that even when full it doesn't last that long, so we have to refill it everyday. And the replacement filters are often not in stock.