Found it – here is the brochure from 2011 which includes the M3-PX.
Also I have a new website that has just gone ‘live’ with some of the components now moving – still work to be done… but if you go ‘loudspeakers’ menu and scroll, you will find my way of describing the various models which shows the cell number used (horizontally) and biggest thing to see or consider for performance is the radiating area which is from left to right descending.