I'm jonesin really hard for a C/CM right now...especially with the new digital back... would be a perfect set up to switch between film backs and a digi back.
My thoughts exactly ... and a good deal of the reason why I ordered the 907x Special Edition set when it was announced in July 2019. I already had the 500CM kit (body, two A12 backs, four lenses, etc) but wasn't using it much without a digital capture solution. Now I'm shooting quite a lot with both the 500CM and the 907x, enjoying it quite a lot!
It will be interesting to learn what the CFV 50 II weighs. It was the weight and the rectangular format that made me decide against the Phase One back.
The A12 back weighs 400g plus or minus a little depending on whether you include film and exactly which series back it is (the dark slide holder on some of the later series backs weighs a couple of grams, etc). The CFVII 50c weighs 650g including the battery, and is about 20mm deeper front to back at its longest point.
The CFVII 50c sensor is 33x44 mm in size, compared to the 56x56 mm film format of the A12, and records ~50 Mpixel in its native full format. However, I usually crop to square format, making it a 33x33mm format @ 39 Mpixel. Still plenty of pixels.
Hasselblad 500CM + CFVII 50c + Makro-Planar CF 120mm f/4 T*
When you do this, switch from the Planar 80mm to the Distagon 50mm to net just about the same field of view on the digital square format with the 500CM/CFVII 50c body. I find that using a focusing screen with the markings for SuperSlide square framing nets just about the right FoV guidelines in the 500CM reflex viewfinder, but of course the CFVII 50c includes a framing guide to fit over the focusing screen on the reflex bodies if you prefer that (and don't swap back and forth between film and digital backs very often).
The most challenging part of using the 500CM/CFVII 50c camera is focusing critically. The big sensor means you still have relatively limited DoF at the usual taking apertures and reveals mis-focusing much more clearly than film capture does, so for best sharpness with the SLR viewfinder when shooting wide open you have to work carefully and get the focus setting right on the money. I find I need the chimney focusing magnifier to really nail it accurately with consistency. (Stopping down two stops from wide open is a good workaround to getting perfect critical focus when you're shooting a little more casually.)
The other option with this digital back is to use the electronic shutter and Live View with focus assist magnification. Then it becomes easy to get absolutely perfect critical focus, at the expense of slowing you down a bit because it works best when you use a tripod to hold the camera.
I'm delighted with the whole setup and really enjoy using both the 907x and the 500CM now. It was an expensive purchase that took a long time to arrive, but is very very satisfying in use. If you click the photo I posted above, it will take you to my Flickr.com album where I'm adding 907x and 500CM photos as they come along.
G