well it sounds like it would be a waste of a tooling if kato didnt use it for other schemes....unless metra specifically ordered these models which i highly doubt. well thats what im hoping.
N Scale Kato MP36 It looks like Kato is doing an MP36 in N scale now......though not in Go Transit just yet.
First pictures of paint http://www.katousa.com/N/SS-Bilevel/index.html If Kato follows through unpainted shell for the MPX will come next summer.