Well thanks to everyone who helped with the planning and analysis of the testing. All of the results and analysis are now up at
The bottom line? 8x10 rules the roost and the challenge is really 4x5 vs IQ180 - personally I think the 4x5 wins but it's close..
p.s some interesting conclusions about differences between 10x8 and 4x5 in my report bit (i.e. almost no difference in resolution once you stop down to an equivalent depth of field of f/32 on 4x5).