When we saw the ML-2855ND rated at 28ppm, we were as sceptical as we usually are. However, while our results didn't quite reach the full 28ppm, we did manage 22.64ppm on our 20-page single-sided document. This was up from 14.29ppm for the five-page test, indicating that the throughput of the printer, once it gets into its stride, is not far short of Samsung's rating. If you print text and graphics, as in our five-page test, you only see about 13.6ppm.
Duplex print is integrated into the ML-2855ND and when selected pages feed partially out of the exit slot and then reverse for the second side to print. This is very normal for duplex lasers and the Samsung machine does it quite neatly, completing a run of our 20-page document, which becomes 10 pages or 20 sides, in 1:38. This gives it a speed of 12.2 sides per minute, or 6.1ppm, which is a reasonable speed for duplex print from this class of machine.
The printer has a physical resolution of 600dpi, which gives a 1,200dpi print under software enhancement. We couldn't see a lot of difference in the dottiness of the images, using our photo test piece, but fine banding across the picture was much more noticeable in the 1,200dpi image. Since the 600dpi print was also two seconds faster, there's little reason for using the finer print mode.
Photos are not the mainstay of a mono laser printer, of course, and business graphics were okay, though there was still some noticeable, fine banding in areas of dark greyscale tone. The paler tints tended to bleach out, too.
Text print, as is pretty much the standard these days for a mono laser, was very clean and sharp and perfectly suitable for external reports and publicity materials, as well as internal, day-to-day correspondence.
As we've said, there are two capacities of combined drum and toner cartridge, one which provides 2,000 pages and the other 5,000 pages. Using the higher capacity cartridge, which gives a better cost per page, gives a figure of 2.23p, including 0.7p for paper.
This isn't a particularly good figure, falling pretty much in the middle of the mid-range band for mono lasers, but there are also several notable machines which don't do as well.
This is a good, general-purpose mono laser printer, with useful features, such as its built-in duplex print. It's compact and still produces pages at well over 20ppm in real office conditions. Print quality for office documentation is fine and running costs fall in the middle of the pack. At under £150, it would sit well in any small workgroup or self-contained office.