As you noted, I mix my own B&W inks. For an example of where I'm at with carbon pigments, see
http://www.paulroark.com/BW-Info/3880-Carbon-Variable-Tone-2015.pdf . Note that I use my generic dilution base with the MIS "Eboni" MK. I actually buy this from STS Inks by the liter, but MIS is the best source for smaller volumes.
For dyes, I use the Epson-Noritsu carts for inputs. My Epson 4000 is set up as a "standard" K2 now but with these dyes. See
http://www.paulroark.com/BW-Info/4000-Noritsu-2K.pdf . The reason for the "color" setup for B&W is due to the dye's relatively weak K. I think the PDF goes into that. I'll have some fade test results on this soon. But, it's in no way in the same category as the carbon pigment prints I'm making, but then neither are some of the commercial B&W inksets.
I basically use dyes for glossy and carbon for matte B&W. The lack of the usually pigment artifacts on glossy paper makes a major difference on some papers, including specifically the metallic papers.
While the lack of artifacts may, by itself, justify the dye approach, note that I have another agenda. I want to clearly separate my markets -- top fine art carbon pigments on cotton, matte paper v. glossy dyes.
Paul
www.PaulRoark.com http://www.paulroark.com/BW-Info/