I'm a renter and my landlord replaces the filter with the least expensive product out there. The place was constantly dusty, even the floors. As an experiment I replaced the filter with a Filtrete. Almost no dust, way less sneezing, and when I changed it again, I could SEE it was doing a good job. What had been all over my apartment (and in my lungs) with the cheap product was trapped in the Filtrete.