Artclay vs.PMC

This talk about PMC and Linda Kaye-Moses’ oblique reference to “the
other clay” makes me wonder, from the perspective of the artist:

What are the differences between Artclay and PMC?

Why would someone choose one over the other?

Christine in Littleton, Massachusetts

It is my understanding that there is not much difference between the
two clays . . . Art Clay hasn’t marketed as aggressively as has PMC.
Art Clay offers some varieties that PMC does not.