one thing…phase one backs +DB shutter are a slight pain in the ass as the back has to be set for zero latency or a 2 shot cable+button must be used. Hasselblad latest generation just works with a sync cord from the shutter.
I have a P65+ digital back on my Arca Swiss 6x9, and yeah, I tried zero latency and found it ate batteries suprisingly fast, the normal latency approach works fine for me, since it on a view camera, an extra step is not a deal killer--after closing and cocking the shutter one hand presses a little button on the cable to wake the CCD up, count to two and press the shutter release with the other hand. I doubt the 2 seconds is all that necessary, but I want to make sure the CCD is truly ready, and if I created any vibrations pushing the wake up button, they have a few seconds to die out.
I also have a Leaf Credo 40, which was my first DB purchase. I decided that for view camera use with mostly film lenses being repurposed for digital, I needed the largest sensor I could get (affordably) since you're not going to find 30mm film lenses for a view camera, in order to get wide, so the larger sensor lets me go down to 50mm (a Mamiya press 50mm ƒ6.3) and still get a decent wide. I also have a couple of 65s and 80sfor mild wide and normal. Anyway in order to still get some use out of the Credo, I bought a Mamiya/Phase One 645DF. I kind of regret that. I should have looked fro the older 645AFD body which can also use film backs.
Anyway the 645DF integrates really well with the Credo, zero latency isn't required and the images get the usual EXIF data from the body. I tried the P65+ on the 645DF, and it worked, but not nearly as integrated as the Credo.