That being said, you will need to do your own tests. I can say that others report that Cineform holds up better over multiple generations, and I personally prefer its treatment of whites to that of Sony MXF.
However, I still find MXF renders quite acceptable, and I would use it confidently with HDV source.
Cineform definitely holds up better after multiple generations. That's what makes my current Cineform problem so frustrating. Right now on my system, only the first generation of Cineform (converted with HD-Link) will actually work on a Vegas timeline. Further generations rendered from Vegas will slow down the crash the system. This problem currently makes the multi-generation capability of Cineform useless, at least until this is fixed.