I've been using the printer for over 6 months. I print 1,000 - 2,000 pages every month. The Samsung ML-2851ND Network-Ready Monochrome Laser Printer works very well for my purposes.
I am running MAC OS 10.5.6 on a computer that is hooked to the printer via USB cable and MAC OS 10.4 on a computer that is hooked to the printer via network. Setup was intuitive. I have not experienced the print smear issues that other reviewers mentioned.
The availability of a 250 Sheet Second Paper Tray (ML-S2850A) <
Samsung 250 Sheet Second Paper Tray for ML-2851ND (ML-S2850A)> was influential in my decision to pick this printer. Thus the printer cost quite a bit more, but it was worth it for me so I didn't have to keep switching paper types in the tray. As a writer I print out a lot of drafts to hand edit. I recycle paper that already has print on one side. I keep one tray with new paper for printing on one side or two sides using the automatic duplex feature and the second tray full of paper to reuse, printing on only one side. I don't print a lot of envelopes, but when I do I just feed them one at a time by hand in the manual feeder, which does not accept more than one page.
Paper jams occur occasionally, more often from the tray with the recycle paper, usually due to paper folding or other defect. On-screen instructions have been very helpful, providing detailed instructions on clearing the jam.
Print cartridge replacement is intuitive. The printer ships with the ML-D2850A Black Toner Cartridge, which prints about 2,000 copies. I've replaced it with the Samsung ML-D2850B Black Toner Cartridge <
Samsung ML-D2850B Black Toner Cartridge for ML-2851ND>, which prints about 5,000 copies. I don't print a lot of images, mostly just text. I've not kept close records on how many copies I've actually printed, but I use the toner save mode for the majority of the printing and my impression was that I was getting a good return on the investment with the larger cartridge, until I ran into a few faulty ones. The company did NOT satisfy me with their response. I eventually just gave up trying to get them to refund my money.
I see that a cheaper high-yield print cartridge REFILL option is available <
1 Black Samsung ML-2850 High Yield Toner Refill Kit, also for ML-2851 ML-D2850B ML-D2850A ML-D2850B INCLUDES RESET CHIP>. From the reviews it looks like the instructions are poor, but once you get the refill system figured out it works pretty well. I'm going to try the refill option next time due to expense and the fact that the company does a crummy job regarding satisfaction guarantee if the product is faulty.