No one else is going to reply to so here is my two cents.
The model's hair looks highly detailed. I can't tell if there is some colour drift (you sometimes get faint green blotching in my experience) because she has used highlights. I will say that she washes her hair too much and uses to much in the way of treatments because it looks very brittle.
And there is the rub. I have always been amazed at the ability of the Foveon sensors to capture texture. Imho, they are difficult to better. I think if you are using a DPxM for portrait work you have to be very careful because what might appear to be a beautiful model in a web-sized shot will turn out to be an over-made-up and manicured crone at 100%!
I stick to things like wood, leafs, rope, rusty steel etc! So much less chance to offend!