I print a lot and have tried them and they work great. I walked half a dozen with 8 more along the way. I keep track of the number of pages printed and get about 3100 prints per cartridge (mostly I print double-sided, so two pages per sheet are counted). If you want to get more prints from a single cartridge, do two things: 1) Shake the toner about every 500 pages. I do this every time I change paper. Make sure you do this outside of the printer because sometimes toner spills out and you don't want it getting inside the printer as it will end up on all your next prints. 2) Make sure you go into printer configuration and set "replace toner" to "continue" instead of the default "stop". This allows the printer to print for a long time when it thinks it is running out of toner, and in fact it will print until the toner runs out, which can be after a few hundred prints. The instructions for the printer tell you how long you have to enter the configuration.
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