I think in studio controlled condition, the ISO50 would be the most beneficial. Smoother tone.
As for RAW, it depends on the workflow. If using DPP and EOS Viewer, it is aware of Parameter settings. The easiest way to tell is to take 2 pictures with -2 Saturation and +2 Saturatoin and view it in EOS Viewer or DPP.
However if you go third party, like Bibble, it ignores it. Either the software doens't know how to interpret it, or by design....



