text: Bought this as a humidifier, the "air cleaning" part is actually false advertising; depending on how hard your water is, sediment does accumulate in the bottom, but none of that is any dust in your home unless you live in a coal mine or something. As a humidifier, I would rate it as slightly less effective than a wick type humidifier with the same fan size. The advantage is that it doesn't consume wicks. Given the additional cost of the unit, you probably have to run it for about 5 years to make the difference up. It does have a fairly large water capacity for its size, since the 'tank' is integral to the unit, and it's low power (although no better than a wick type). It is also fairly easy to clean, although the plastic disks can't really be serviced since the disk unit can't be disassembled. However, for German engineering, the build quality isn't great. I've had mine for a year now, which would be about six months of cold weather run time, and the unit has developed a very annoying rattling noise from the fan assembly. My guess would be the fan bearings, so I'm just waiting for complete failure to happen here. As noted by someone else, any repairs are almost equivalent to just buying a new wick humidifier. tl; dr - not worth the extra cost, you are better off with a wick humidifier.