Wayfair service was perfect, purifiers arrived earlier than expected.  The TruAir units look good, are reasonably quiet, use less current than I would expect (measured 12, 25 or 50 watts).  It arrears to me that they blow the air in such a way that it will mostly just swirl around the unit itself without circulating the air through the room.  So, do they do their job?  I don't know.