Conclusion: The OKI C5400dtn is a champ at paper handling, with a duplexer and 930-sheet capacity. Unfortunately, it drops the ball on basics, most notably text-output quality, where it isn't a match for most color lasers. It also choked on some files in PCL mode, although it printed them in PostScript.
Pros: Comes with both PCL and PostScript drivers. Good paper handling, including duplexer and 930-sheet paper capacity.
Cons: Text output quality is below par for a color laser printer. Failed to print our PDF and PowerPoint files using its PCL driver.
Summary: The C5400n shares the C5200n's decent paper handling and robust duty cycle, but also its compromised colour print quality. This won't endear it to the sort of users that need its PostScript support, except where low running costs are paramount.