@niels The Clairefontaine DCP looks very well behaved.

We have some very good options listed here. I continue to practice with the Kokuyo KB and have no issues with it. While not as smooth as Rhodia, it’s smooth, and not toothy at all. I also haven’t encountered much in the way of feathering using a variety of inks (Diamine Oxford Blue, Pilot Shin Kai, J. Herbin Bleu des Profondeurs, and Waterman Mysterious Blue).