Printer wasn't behaving particularly well for a while. I cleaned and vacuumed and dusted and all, but still had marks on printed page. Then the advisory popped up that I needed "replace drum." That procedure in the manual looked almost as scary as the price. But given that I'd already messed around with it as much as I had, I figured that I'd try that. Installation is MUCH simpler than the pictures or instructions indicated, therefore much faster and now the printer is delivering like new. Shoulda tried that first. I even found out that Brother will take the old drum back for recycling and they'll send a prepaid label to do it. BONUS!