I bulk load film, and I use plastic film cans to protect the bulkloaded film from grit. As soon as I load the rolls, they go into the plastic canisters. This protects the cannister's felt, keeping it clean while film jostles around in your camera bag.(posted 8452 days ago)Since I've followed this practice, I've had almost no problems with scratches. I'm also comfortable re-using the cannisters over and over since this practice keeps them so clean. I use the plastic, screw-top cannisters.
I don't have a good use yet for the aluminum film cans. They sure are nice cans, though.