Purchased to remove dust, allergens and pet hair etc. The filters came exceptionally well packaged. Easy to open and quick to set up. The units are reasonably quiet. Not noiseless but not intrusively loud. My previous filters which I replaced with these were very loud. 
 
I love the automatic mode. The self adjustment is wonderful. I am noticing improvements over my previous units. I would be most stuffy waking up in the mornings. I have had the units running for a week now and this has been reducing day by day. It is winter now but I'm expecting pollen season to go much better this year.