I had to change my CCC unit as it developed fault. I checked for available options to me, so I know from research that CIC and NBT upgrades are possible for E60, if one is willing to put in effort and time.
However, the parts are prohibitively expensive here in KSA. So I bought and shipped a used CCC unit from US. I didnt opt for CIC in the end, as the installation is quite involved, and I didnt come across anyone proficient in coding locally.
Hell, till date my iDrive controller does not work, as it needs some coding to be compativle with the installed CCC. I am trying to get some remote coding done from US, so lets see when it can be done.
What is your reason for changing?
If you need any parts, I would recommend getting them from US or Germany directly. I searched EBay and bought a unit.
Check out my BMW E60 ride thread.