The orig. manufacturing company has discontinued this particular drum unit so we have to purchase a refurbished drums. When buying from the manufacturer (approx. $170/unit) the unit lasts for 1-1.5yrs with pretty heavy use. These refurbished drums only last a few months. With our last purchase 1 drum was damaged and makes marks on all pages it prints When the units are new they work great but don?t last long, they claim 20,000 pages but it seems more like 3,000-5,000 pages before the drum needs to be replaced again. Unfortunately because it?s no longer available through the manufacturer this is our only option.