This often overlooked issue is easily solveable. Since the whole computer system is based on the SI system, which only standardized unit/time, every other option is a non-standard invention by some computer engineers.
So if you see people using anything else than kb/s, kB/s, they are wrong.
However, the IEC’s standards are not SI’s, so Kibit/s instead of just Kib/s could be acceptable.
