Digital BW, The Print

The Cone site implies that MIS inks might have a higher pH and are more
prone to Metamerism:

From the Cone site:

"Piezography\ufffdinks are not subject to the metamerism found in dye based
inks nor dye/pigment inks. Metamerism is the tendency for an ink system
to appear different under varying light conditions. For example,
Piezography\ufffd prints do not change dramatically under tungsten,
fluorescent and incandescent light sources. The same can not be said for
ink systems produced by EPSON, LYSON, MIS and others. Additionally, our
inks have a pH basic rating of 9 which makes them EPSON compatible.
Competing inks are often acidic."