After putting up with unbearable dust for the past 4 years, after moving into a new condo, we bought a 1700 3M Filtrete air/furnace filter. Now I'm wondering how we ever lived without it. I cleaned the entire house, vaccuumed, dusted, etc.. then we installed the new filter. The difference was so dramatic its hard to describe. All I can say is you have to try it to believe it.