Before we started using your product, we were using the "everyday, basement bargain brand" of air filters. Wherever we could get them at a good price, we purchase 'em by the case. After learning of my father's diagnosis of COPD (Chronic Obstructive Pulmonary Disease), we started using Filtrete Air Filters. We noticed that the air quality in the entire house was different and my father was breathing easier. When we received service on our HVAC system, the technician said that "we must be changing our filters every week!" Needless to say, we'd rather spend a little more for better air quality than to pay for a new HVAC system.