The unit uses charcoal and a HEPA filter to clean the air. Prices range from $140 to $180 at online shops. A five year warranty is included.
A cleanable filter will eliminate the cost of replacing the expensive filter which can reduce the lifetime cost of the machine.
Users claim that it does a very good job of removing odors and helping allergies. The most common complaint is that the unit can be quite loud however this can be a benefit to some who desire a lot of white noise.