I cut a lot of plywood and for that the filters are sub par. They clogged up pretty quickly. The combined filter is not manufactured the best. They pack it well during shipping but the metal is usually bent in some way or the metal rivets interfere and do not allow the pre- filters to be inserted or removed easily. I have a cyclone unit and a matte filter on top of the pre-filter and the hepa filter and I still need a mask and proper ventilation in order to use the unit for production use. Filters are very pricey to replace and It I wait for Bofa unit light to tell me the filters are getting clogged then it’s already to late. At that point. You might as replace all the filters at once.