There's really no point to using a swab because it isn't long enough to come out the bottom and put lubricant where it's really needed...on the sizing lip at the bottom of the die. The sides of the hulls don't need lube.
A good brush won't shed bristles but there's really nothing to brush out of the dies anyway. Clean plastic hulls don't deposit anything in the dies and I don't put dirty hulls in my presses.
I stopped using both and just remove the dies from the turret every couple thousand shells and give them a cleaning with Ed's Red. Removing those obstructions gives me a clear view of the hulls as they enter the last 2 stations.
I have a 10 ga bore brush of brass (or whatever they make those things out of) and I insert that into my Makita. then as I load I bring the handle down and let it stay down. Then I remove the empty die that is about to accept another empty hull. I scrub the die form both ends and blow it out. I then do that procedure for all the dies as I load. Pretty quick it is. I have one die marked with a magic marker to know which one I started with. I have not had to clean the dies since I started this program. And that is about 2 flats ago. How often will I do it? Prob when I think the hulls are beginning to hang up. couple thou maybe?
A bronze chamber brush works really well. You do not need to leave it on the loader all the time. Just put it on when you notice the shells are getting hard to push out of the shell holder. Quicker than removing the shell holders for cleaning.
The brush that P/W provides is not big enough to really clean the shell holder.