I bought the Radian toner cartridge to replace my aging Lexmark toner cartridge. The Radian cartridge has lasted a measly three months - keep in mind that a laser printer toner should be good for six thousand copies - and did a tour of duty of about five hundred prints. Now, the cartridge has littered my printer with dust residue and has caused only entirly black pages to print. This cartridge is a horrible piece of crap! Avoid it at all costs, especially since it costs almost $100.