Canon’s speed claims for the i-SENSYS LBP5100 are modest at 12ppm for black and 10ppm for colour. Our five-page black text print took 44 seconds, which gives a real-world speed of 6.82ppm, but when we increased the page count to 20 pages, the printer managed it in 1:58, or 10.17ppm, pretty close to the claim.
Colour print took only slightly little longer, with our five-page print completing in 46 seconds, so we would expect to see the same speed increase with longer documents. While this isn't a rip-roaringly fast printer, at least it's quite close to Canon’s specifications.
It's unusual to have a colour laser printer at this price that supports double-sided print, but Canon's implementation is also designed to print quickly. The printer effectively has two output slots and draws the page it’s about to print the second side of back in, at the same time as feeding out the previous, completed page. This speeds the whole process up and we completed our 20-side duplex test job in 2:14, only 16 seconds longer than the equivalent 20-page, single-sided test.
Text print is clean and densely black at the printer's default resolution of 600dpi and there's no sign of toner spatter, which would give it a fuzzy outline. Colour print is very bright which, while it makes graphics stand out, isn't very accurate to any images printed. Blue in particular comes through much darker than the source colour and registration between black text and any underlying colour tone isn't wonderful. While you can make adjustments in software for some compensation, it should be better by default.
Photo output, by contrast, is if anything slightly underplayed, with colours looking reasonably natural, but with a lack of life. We put this down to an unimpressive yellow content and dark print. A 15 x 10cm photo took 24 seconds to produce.
The only consumable cost is the drum and toner cartridges, which are available in a single capacity: 2,500 pages for black and 2,000 for each colour. With the prices we could find for them on the Internet, we calculate page costs of 2.4p for black and 9.01p for colour.
These costs put the LBP5100 pretty much in the middle of the field, when compared with colour laser printers at similar prices. We can find examples of machines costing more and less than this one, but it all depends on the consumables price you can find. It's well worth shopping around to get the keenest quote.
Canon has produced a quality printer in the i-SENSYS LBP5100. It's easy to maintain, is mid-range on consumable costs and lower than many of its rivals on initial purchase. While it may not be blisteringly fast and may need a little adjustment to get colour output right, its ability to print duplex pages with a minimum of fuss makes it an interesting proposition. You should add in potential paper savings to any purchase decision based on cost and you may well then find it's the most economical choice.