I just looked on ebay and picked up bought a few boxes of grade 2 and 3. I will print a few step wedges with different developers and toning methods and then measure Lab values to see what inkset will best approximate the color of a few different papers, Azo, Portriga, Ilford,
I think the best way to go about this is to set up an Epson x800 or x880 with a mix of a shared black (MK/PK) and two different color sets of the same three shades. An example would be shared shade 1, and one set of carbon shades 2, 4, and 6, and one set of selenium shades 2, 4, and 6. When i get some free time i plan on testing which three shades of grey work best with this configuration.
I don't mean to be a Jon Cone cheerleader here, it is just that those are the inks I have, and he is very clear about what each inkset includes and that the L* values of each shade are the same from one color inkset to the next.
I would love to have a 2880 and a few different sets of refillable carts to experiment with all the variations of MIS Assoc. inks. and mess with mixing my own and comparing them to the Cone inks. Maybe this winter.