Thanks for advice. I've always liked 6x6 square and I have almost decided against 645, while 6x7 would be lovely though I am not sure about the weight of a Mamiya - still it weighs just a little less than a D200 with an 80-200 lens. Or a loaded Ebony.

After a few hours of trawling the sadly favourite auction site I narrowed down my choices to a Bronica SQ Ai or a Mamiya RZ67 Pro II or RB67 Pro S. Ideally in a superb state without too much heavy-duty use and with some lenses, 80, 120, 150ish, and perhaps a 40-50. With a budget of €600 or so.

If anyone would like to steer me away/towards either Mamiyas or the Bronica I would very much welcome your comments, no matter how subjective.