Hey Robert, sorry I did not see your question sooner. The Uni-Ball does work with conversion varnish and 2K auto clears, as do the Microns. The Uni-Ball also comes in gold, silver and some other cool colors.
The thing to do is get yourself a few different brands and tip sizes, then experiment to see which suits you best. But if you have the skills like Eric, nothing looks as good as India ink and a nib.
The One Shot letter paint that Brad uses is indeed good stuff, but be careful if you use it. It use to contain lead, don't know if it still does. I know it contains heavy metal driers and a variety of nasty solvents. Stuff lasts a long time, even exposed to the elements!