I just did a *very quick* test with the 4K Raw and my 5D Mark II RAW (still image). I stress very quick because really hold judgements until a professional has had a go with it.
This is conducted with a 4K camera that doesn't have noticeable FPN during regular use, so I imagine it's about as ideal as the cameras come.
By changing and watching the Zebra I can say the screen here triggers the zebras at 85%, but not 90%. Hopefully that gives you some idea of the range in the image. So it's not just about to clip, but it's as bright & dark of an image as I could get quickly right now.
As far as Dynamic Range goes with the RAW files, there was no room to move with the shadows. As soon as I pushed them up even slightly, the FPN pattern was there, literally lurking in the shadows. It's great that it's not visible in the image as-is, but it does limit you to not bringing any shadows up.
Highlights however offered room to move, but again these appeared to be about 85% as bright as the camera can handle. In Lightroom at least, the histogram appeared up against the left and the right, and while I couldn't bring up even the lighter shadow areas, I could pull down the highlights quite a bit.
I tried to compare it to a ProRes Film still but there didn't appear to be much of a difference in the dynamic range, just a little extra. However please *wait* for someone to do a proper test, because I can barely use Resolve at all. I'm very handy with Lightroom, but honestly a complete beginner in Resolve.
Compared to my 5D Mark II raw image, the dynamic range seemed a bit better on the Canon. And that was also taken at ISO 400, so there might be a tad more again if it was ISO 100. But there's certainly more room to push and pull. Mess with the shadow areas too much and you get Canon's pattern noise, but you have to go quite far before you hit that.
Interestingly just going off the back of the LCD screen, I would have sworn the Canon had much less dynamic range. But it shows how misleading the screen can be, oh and it helps that the Blackmagic screen was in Film mode, haha.
Edited RAW file (jpg 100% quality):
http://img.acianetmedia.com/i/753Bd.jpgOriginal RAW file (jpg 100% quality):
http://img.acianetmedia.com/i/GajTD.jpgEdited 5D Mark II RAW file (jpg 100% quality, 16:9):
http://img.acianetmedia.com/i/OAyIg.jpgOriginal 5D Mark II RAW file (jpg 100% quality, 16:9):
http://img.acianetmedia.com/i/BcG3W.jpg