I received this purifier free in exchange of a review.  I've been given other premium purifiers before, and this one is the best.  There is a quiet mode that is genuinely quiet, and still makes the room feel and smell clean.  It's wonderful.  I keep this one in my bedroom and I can sleep with it on.  It's pollen season now, and it is truly doing a fantastic job.  I also have 2 dogs, and it keeps up with them PLUS the pollen.  I love it.