Is the Model Masters acrylic or enamel? I've made the mistake of grabbing enamel instead of acrylic a couple of times because the labels are similar. If it as acrylic, and it's not working for you, the Citadels do cover nicely and go on pretty smooth. I also find it easier to match skin tones with Citadel. The one catch is that they will sometimes rub off with too much contact unless you use a clear varnish to seal them. Almost any brand of paint will need to be thinned out with water if you want to avoid brush marks and chunkiness, though.