The duplex scan, print and copy features of the DCP-9045CDN do pretty much what they say on the box. You can print on both sides of the paper in a single job, scan both sides of a document from the ADF, though obviously not from the scanner glass, and copy a duplex original. You can also take a single-sided document and produce a duplex copy. It's a comprehensive set and although not that quick, it does all these jobs well.
Brother rates the device at 20ppm for both mono and colour print, but our five-page black text document only provoked 12.5ppm under test. The 20-page job increased the speed to 15.58ppm, but this is still only around 75 percent of the rated speed. The colour text and graphics document returned a speed of 9.68ppm, less than half the headline rate.
Duplex printing saw a speed of 6.90 sides per minute, disappointingly slow as it may discourage duplex use, in favour of faster print speed. This slow duplex speed is reflected in the 10-page/20-side document copy, which took a sluggish 3:18 to complete. After the initial novelty of the scanner feeding out pages through its top slot, to handle scanning of their second sides, it turns out to be a coffee-break function.
Having noted these speeds, it's worth comparing them with the Dell 2145cn, a machine aimed at a very similar market segment and sporting duplex scanning as well as print, like the DCP-9045CDN. The Brother machine beat the Dell in every speed test, sometimes by a substantial margin, as with the five-page black text document, which returned only 7.32ppm on the big black machine, to the Brother's 12.5ppm.
Print quality from the DCP-9045CDN is what we've come to expect from Brother machines. Black text is sharp and clean and well up to use in external, as well as inter-office documents. Colour graphics are also good and while being bright enough to attract attention are not so vivid as to look gaudy. The photographic samples benefit, too, looking more natural, even a little too pastel. There's plenty of detail in brightly lit and shadowed areas of images.
Maintenance of the machine is a bit more complex than some, with toner cartridges, a drum, a transfer belt and a waste toner cartridge all having different service lives. Adding up the cost of all parts gives a cost per page of 3.17p for ISO black pages and 10.81p for colour. Comparing these with the costs from the Dell 2145cn gives very similar results; slightly more expensive on black, slightly cheaper on colour.
This is an impressive multifunction device, with many of the features needed in a modern office. It's useful to have the facility for duplex copy and scan, as well as print, though the copy speed is disappointing. Even so, the print quality and ease of use of the machine makes it a good choice for general-purpose document printing.