I've used Nason products for a few years and no complaints here, painted my 32 frame with ful-thane urethane, and just painted my 31 coupe with Nason acrylic enamel, using the 483-11 ful cryl catalyst. No complaints, only problems I had was operator induced, like forgetting to use fisheye eliminator the First time I painted my frame.
P.S. About base coat clear coat , I can't stand them, I have painted a couple newer cars with it, don't like it, but of course I grew up using the old stuff, so I'm a little bias.