I used the DigiFlex II with a CF39 (amont others). I often let the black edges attached as an artistic thing
It can be quite nice. The 'gate' is several mm's larger the 24x36. If you crop the edges off you still end up with a good 20MP file and on occassion if you can stand some fall-off you can get to almost 30MP.
I have used the DFII for years, it was my main workhorse. If you get the hang of focussing and like a simple, reliable camera with only basic controls (I certainly do) it is a very fun thing to use.
My experience is that the wider the lens the less the image circle with these Nikons. Most lenses from 24mm and above have adequate image circle. I have sold my last DF somewhere last year.