A really cool idea, I'll let the other reviews speak for its convenience.
But before you buy, check the web, these printers do suffer from streaks which you can minimise to some degree (tends to only really be noticeable in dark areas of the photo). Use the blue paper to clean the print heads (may need to do this regularly).
Also note - All zink paper has a short shelf life (6months), so don't go buying too much of it. The packs I got also had conflicting date on the outside and inside of the boxes (later discovered that the inside date are not expiry dates but production dates despite saying best before).
But still, for me, worth the 25 quid (the product is really as easy to use as advertised).