When I got back in the model RR scene in 2005, I was surprised to see how much Floquil took a back seat to Polly Scale paints (or "Polly S as it was known back in the old days (late 70's) with the parrot & music scale-"It's from Polly S."
I used Floquil back then as a rule, especially since the variety was better than Polly S back then (tables have turned) & of course, used the Floquil "Barrier" since I was working w/plastic, & brush painted. I really didn't have a problem when the Floquil encountered "unBarriered" plastic on a small area, but once when I tried to strip off unwanted paint with the Floquil thinner, I turned an Athearn 40' boxcar side into something that looked like it was treated w/a blowtorch!
I'm wanting to say I used mineral spirits, or plain old paint thinner too back then with no ill effects (on cleaning brushes that is), but my memory's grow dim-as to airbrushes...what are those? ;D