Came across a luggage system called Tactuff. The rack fixing system would seem to be identical to the Mezzo system. A range of rack top bags are available and also an adapter that can be fixed to other makes of racks meaning that if the system is the same, Mezzo bags could be used on other bikes.





This company seems to be the distributer in the UK.
http://www.actionleisuregear.co.uk/index.php

This is the manufacturer.
http://www.lotus-bag.com/