Thanks for your thoughts!
Nice to hear it´s possible to use the Arcbody with a digital back.
But to switch back between the Arcbody and Contax will not be practical as you write Morgan.
It´s not actual to sell the Contax system, two bodies, several lenses, auto bellows and so on. And the cameras works very well for me.
I will take a look at Alpa at Photokina, I´m using a Roundshot 220 from the same manufacturer.