I have never been a fan of adding Carbon Fibre parts, Gloss Black ones or Matt Black ones. Carbon Fibre to my eyes looks naff, the Gloss Black gets scratched easily and produces a look on cars suitable for a B Class horror movie and Matt Black ones look cheap DIY.
If it was not such a hassle, I would seriously consider changing some of the Gloss Black trim on my M Sport to Chrome, except for the Rear Diffuser which I'd leave well alone. I wish BMW could have given me this as a no cost option.
To keep the peace, I end by saying ETTO.