I ordered the boot storage shelf from my local dealer (Western Mazda, Edinburgh) and was surprised it was only £9.60 compared with £30-odd quid online.
http://mazda-2.sgpetch.co.uk/pages/accessories/detail/model=375/category=interior/accessory=Trunk+Storage+Shelf/id=4894Anyway, it is a good addition to the meagre storage in the car. It fits with strong velcro, but I've just left mine sat on top of the boot surround and it doesn't rattle at all. I put my owner-wallet thing in there, plus some cleaning gear/cloths etc and there is room for loads more. I'd recomend it. Frees up a lot of room in the glove-box.
PS: Also got a true-red touch-up kit for £6.