I have been using these for about 15 years now and love them. You would be amazed at how much stuff you can see trapped in one even after just a month. It will remove pollen, and even smoke and mold from the air. I would suggest getting a few for a season, especially if you dodn't have central air and are running the heat for the first time in the fall with a filter this fine. You will probably end up changing the first one after a month, then ever 3 after that unless there are constant pollutants in your house, like a lot of smoke or a mold problem.
Used the Filtrete 2200 1" MPR filter until we had the furnace/air conditioner system replaced last year which has a 4" filter but the Filtrete 4" filter maximum filtration is a 1550 MPR...wish it came in the 2200 MPR.
The Filtrete 1550 Allergy Reduction filter does a remarkable job in filtering out the seasonal mountain allergens that blow into our North Central TX home. We use fewer antihistamines since we have installed the high efficiency filters. Thank you, 3M.
I bought this product because it was the right size to replace my Electronic Air Filter, that had died. I installed it and all seemed well. After about 1 month I noticed the A/C unit was running continuously and the temp in the house was going Up. I noticed that very little air was coming out of the vents. Turns out that the filter material had sort of Swollen-up and cut the width of the 'pleats' by more than half. Basically, it was like having a 30-day filter in your furnace for a year! After de-frosting the unit and mopping up all the water, all is now normal with a different filter. I would like my $30+ back please!