A little bit of perhaps old news to those of you who long ago left the Phase One 645AF body behind. I picked up a DF body today and all I can say is wow! The focus performance is incredible compared to the AF. It is working well with my IQ140 without locking up, or any other signs of misbehavior. The camera has firmware V1.21 on it (my back is on V5.00.51 to support the 645AF body).
I don't see a reason to update the firmware at this point in time. The only thing "not working" are the custom functions... I can't adjust any of them (other than C-00)!
I swapped out the focus screen for the Mamiya "Type C" with microprism and like the results.
So far I'm a very happy shooter with this upgrade.
One question - flash sync speed is no longer firmware adjustable - it looks like X-sync is 1/80th sec. Does that sound right? I hope to not bump the function dial now that it doesn't have the lock... little things I think I'll be fine with.
Cheers everyone, and Happy Holidays!