The airfree units don't move much air and that is the main concern with this type of technology. Can it effectively filter all of the air in a room within x amounts of hours? The manufacture claims that it takes a few days but eventually all of the air is filtered. Compare that to UV air purifiers that can filter all of the air 4-7 times an hour in a bedroom. Yes, the Airfree units are silent, and that's a plus. Yes, no replacement filters or UV lamps, and that's a plus. However, do they do a good enough job of sanitizing the air in everyday living conditions when dust and allergens are being kicked up all the time as we move around a room? Probably not.
I can't remember the original type of air purifier you bought from us, I think it was a UV induct unit. How is that working out for you? Why don't you just run your HVAC fan all the time and change your furnace filter once a month, what we recommend as the best value?