[jaapv]

I think if the focus throw and with that the slope of the cam are adapted to the limitations of the M8, focussing accuracy will not be a problem. The main problem we are seeing now is that the lenses that have been designed for older cameras with the less accurate film as receptor and another rangefinder configuration are touching on the limits of the system. Lenses being designed now will certainly take that into account.
Having said that, all my lenses, including the 75 Summilux, are quite accurate on both my M8 bodies.
It may well be that older M8s need to be adjusted on the new adjustment rig Leica built a few months ago.