After considering the options I've purchased genuine Honda 2009 mats via eBay - £43.55 including delivery (next day).
My feedback on fitting: As the instructions lost something in the translation I took an hour on the first one. The next three took less than 20 minutes in total.
Positioning and fitting the holders into the carpet is easy but it needs to be done with care. On the driver's side the rubber/plastic pad under the pedals has parallel slits already cut into it. There are indentations where all other cuts have to made (the rear passenger mats fit without clips). All cuts I made with the aid of a steel ruler, as a cutting edge, and a utility/craft knife.
The carpet has an attached fibre underlay and for the first holder and I spent time cutting this away from under the recess (Honda's word). Wrong: Inserting the bottom section of the holder under the combined thickness of both the carpet and underlay made it impossible to fold and lock it down.
The answer I realised was to separate the top part of the carpet from the underlay (with a finger) and then feed the holder between the two layers. The holder then clicked shut easily. From then on it was plain sailing.
For removing sand, grit (and volcanic detritus?) 'factory' mats unclip and lift out easily for shaking and beating. I've had them on other Honda's and there have been no wear problems.
