I am using the P45+ with an H1 and I like it very much. At some point I do want to upgrade the firmware to get the mirror delay feature. I think it would help shooting handheld with available light. I love the lenses. The 50-110 Zoom is really nice and is one reason I went with it. The 100 f2.2 is really nice with a fast f stop.
The only things is Hasselblad has locked us out of using the 28mm lens. But the 35mm is pretty wide.
I am trying to get used to the new Phase One C1 Pro software, they do have lens profiles for the H series lenses.
None of the new Hasselblad Camera Bodies being made will support Phase One backs, but they will fix them and they are easy to get used.
I am using the newer/better 7.2 volt rechargeable batteries with the H1 body too.