I purchased a 220 ml matt k cartridge from STS Sucked it dry.. I made uo a standard C6 inkset. no K in the yellow. I am by far no expert but I love to fiddle.
I made up a 21 step profile for arches BRT White. There was a slight increase in Dmax When compared to the MIS C6 in run in another 1400. The STS profile was dead straight before linerizing. Using the North light 51 step tst print The STS is definitely the stronger print.I have not yet created QTR profile.
I also made up a C6 STS K+MIS 2 K ink set. I got a 1.63 dmax using Paul's QTR profiles.
Using the straight STS ink set and addiding K in the Yellow I got a 1.69 dmax.
I also tested with Han German etch. and got a 1.75 Dmax and a very nice 51 test print. I did not test Paul's Icc's yet.
These t tests may not be a valid way to test, and are definitely subjective. they may also be in the realm of opinions. And we know what they are worth.
But as Paul says "Enjoy the Journey"
Kelly
A footnote I am using a Spyder for the profiles