I have only used 1 washable air filter before; This is because after washing the 1 filter once, I realized I would never do it again. A washable air filter, in theory, sounds like a great idea. You’ve got your Heating and A/C component that is churning up dust. The air filter is meant to catch it before it goes into the system, but so congested thought, that once a month the filter needs to be taken care of. A washable filter allows you to wash it and keep it. You can do this for about three month. Otherwise, you need to buy new. It sounds like you are getting quite a deal. You are saving months of air filters by using the same 1. Washing the a/c filter is a pain in the butt though. You have to remove the air filter from the screen as well as then try to clean in between the holes. It took over an hour to detach, clean as well as reteach the filter. After all of it it seemed any cleaner. Air filters are not that fancy, however even if you get the pricy HEPA filters that deal with air quality, you are not spending that much, then honestly, I would rather spend $40 a month to not clean an air filter. It is worth it to me. What I do is just stock up on Heating and A/C filters.