Thanks for your feedback.

The only way (I found out with my Vallejo black) to paint Model Color, with an airbrush is to the dilute a lot with black wash. It seems to work OK - not great just OK. Model Air is better fir that, of course.

I've fairly good luck with reds and yellow, as long as my under color is a white or even a silver, believe it or not.

I tried the Inktensity for airbrush. It covers very well! I think those paints are mostly used by gamers, since that is the type of store I got them from. (I know next to zero about those games).

Inktensity has a very opaque coverage and does not require a multilayer buildup. Should one chose to buildup I'm sure that would be possible to do so.

I'm still a Vallejo guy with a few other brands scattered about.

I understand that certain brands do not appeal to certain modelers, so I guess that's why there are a number of brands to chose from.