Not a bad idea, filters have changed a lot in recent years and some of the newer brands (phresh, phat etc.) use crushed carbon instead of granular, and these can have some extra dust come off of them.
Well have it out in the garage right now pulling air through it. Not much dust. Figure I'll run it for about 10 - 15 minutes, then go hang it up. It's a 6 inch filter and 400 cfm fan set up. Looking forward to cooler temps and fresh air exchange with no odors.