A C100 Mkiii would have to do better than 8-bit internal these days to get my money. As a dedicated cine camera, it now would have to have a better codec than, say, the GH5s internal. It also needs to better the 8-bit codec in my 5Dmkiv, which is more of a stills cam with decent video functionality.
With the main draw of the C200 being RAW, I'd be looking at at least 10-bit 4:2:2 at a decent bit rate, but not raw, from a C100 Mkiii, otherwise I'd simply stick with my 5Dmkiv, or save a bit more for a C200 and a lot of storage.