Just a minor point of correction to the previous review that addresses the distinction between the DRUM units and the TONER cartridges: first, when you purchase the printer, it arrives with 4 drum units that ALREADY HAVE "STARTER" TONER CARTRIDGES IN THEM. This may be lead to some of the confusion, but, yes, they are distinctly separate products. Second, the previous review indicates that the drum units are good for "5,000" pages and that you would therefore replace the toner cartridges 3 times before replacing the drum. In point of fact, the drum life is rated at "15,000" pages. Consequently, you would replace the toner 8-9 times IF you use the TN-160 toner product --rated at 1,600 pages-- or closer to 6-7 times if you use the more economical TN-210 product which is rated for 2,100 pages.