I have a cord and a flex, and also a Microcord 1 1/2, to be honest I prefer the microcord, apart from the difference in that my Rolleicord va2 has the dreaded exposure value systenm and setting/releasing shutter beneath the lens there really is no difference in the results between the 2, my cord is easier to focus than the flex in that my cord has a split image as per a SLR, but that is all, as far as the brightness of the screen there is no difference, as far as the weight, very little difference, but the results with my Microcord, with the Ross xpres lens, is slightly better than either of the rollei's, the focus screen in the Microcord is a little dimmer, but that can be easily addressed if it becomes a problem, as far as the winding, having both the winding and focus on the same side I find easier, you just have a large button in the middle of the winder to release it, winds perfectly, I would suggest that given the choice I would pick a Microcord over a Rollei any time
Richard