My Rolleicord IV is my current MF shooter and I can say mostly good things about it. Before I sold it I had a V too, both behaved rather similarly. Small, light, universal cameras that pack a lot of potential image quality. Using them is a pleasure.
If I have to describe these boxes with one word it would be " well ballanced": wide open it's already more than usable, but still perfect for portraits, sharp enough without being offending; f/11 1/2 - f/16 represent the optimum apertures, by which it gets sharp enough for I think most purposes. At f/11 the image almost everywhere is sharp, but the very corners will improve a bit by stopping down further to f/16. This is pretty much predictable. Even the centre gets crisper by stopping down this much, not only the outer zones.
I made sectional enlargements a couple of days ago from an FP4+ (developed in Rodinal 1+50) negative that I shot at f/8 and 1/60th handheld. Focus was at infinity (centre of frame). A 17x enlargement from that section was excellent, the corners were noticably softer, but not bad in any way. At this magnification microcontrast is lower, but all the detail I need is present.
Had I the camera on a tripod, stopped down to f/11-f/16, using for example Delta 100, the results would have been even better. I most happily use it for critical photography this way.
All in all, this camera/lens is good enough for most purposes, but if you're looking very close for some softness, you can find it.