I've noticed one phenomenon that holds true across pens, nib widths, flow, and choice of paper: take-sumi is more prone to feathering that tsuki-yo. If one pen can't handle take-sumi, I ink it up with the tsuki-yo and the problem of feathering is solved. For this reason, I use the tsuki-yo as a "therapeutic" ink.
Has anyone had this experience? I have only used these two inks. Would you be able to rank feather-proneness across the inks?
More importantly, how does Kon-peki do when compared to take-sumi or tsuki-yo?