Been using the Airdog X5 for a couple of weeks. It is a quiet unit, the highest fan speed is a bit loud. It moves a lot of air, seems to be less dust and dander from 2 cats flying around. Cleaning the unit is very easy, no hepa to buy. so far so good.
Wonderful clean air. Dust has been reduced greatly. Unit will eventually pay for itself, in not having to buy the expensive filters like the other brands need.