PLANon rates the PrintStik PS910 at 3ppm, but it took us 1:01 to produce a single text page and 1:24 for a page of text and graphics. A 15 by 10cm photo print took a pretty long-winded 2:43. The printer is designed to stop as soon as it sees blank paper at the bottom of a page, to save on thermal paper, but this does make it hard to print full sheets. There's no automatic cutter, either, so it's up to you to tear off a page at the appropriate length, when it's complete.
So, the printer is slow, and also noisy. The kicking it makes as each line of dots is created is rather different from the noises made by inkjet or laser machines and isn't particularly unpleasant, but it is noticeably loud.
The worst aspect of the printer, though, is the quality of the print produced. It harks back to much earlier days, when prints were only an approximation to the file on screen. Text is dotty, incomplete and irregular, with few characters having complete outlines. While it is readable, it looks decidedly tatty and is only really useful for keeping drafts of documents.
Greyscale graphics can hardly be called greyscale at all, since the patterns of dots which make up different shades are so coarse they look more like cloth textures than shades of grey. Text on top of greyscale fills is almost impossible to read.
Trying to print a photographic image resulted in a grainy, dotty picture with streaks in darker areas and obvious changes of dot pattern in areas of sky. Because the thin, thermal paper is so tightly rolled inside the printer, all the prints come out with a pronounced curl, too, and need to be re-rolled the other way, to flatten them out.
Six rolls of paper, each of which should print 19 or 20 A4 pages, cost £19, giving a cost per page of 15.82p. Although this is high - a typical inkjet page costs under 4p - it's irrespective of the coverage on the paper, so a full A4 photo will cost no more than a page of text. Quite why you'd want to print an A4 photo on this machine is another question.
Looking at its potential competition, it's surprising to discover that portable printing is one of the areas of the printer market which are shrinking. There used to be several more models than there are now and your choice is between the PrintStik, Canon's PIXMA iP100 and HP's OfficeJet H470. HP's offering is noticeably cheaper than the PrintStik, but also considerably more bulky, while Canon's machine is also comparatively large and costs £330.
In both the inkjets' favour is that they use conventional liquid ink and can produce colour as well as black-and-white prints. They print on plain paper, too, and can even produce colour photos at a pinch.
If you really need a printer which takes up very little room and can print autonomously, without external power or paper, the PrintStik is pretty much your only choice. For any other portable application, though, we'd looked elsewhere.