matte is non glossy. there are ussually three types of paint out there with varying luster; matte, Satin-Gloss and Gloss.
Im not sure about gundam paints since I have no experience to speak off to judge its quality, maybe we could ask some of the modelers on model making threads, they probably have a greater grasp on the subject than I do. check if it says "acrylic", its probably workable
with regards to Shazam; I think I may have a sure fire recipe (inspired by Lance's work) which would minimize paint application for him. though it would take a substantial number of figs to slice up to do so, the onset of Black Dragon's cheap supply of custom fodders make this feasible
Superman head (re-sculpt the hair line)
Orion body
Aquaman wrist bands
Aztek boots
JLords manhunter cape (spray painted white)
just cut and glue when appropriate
hope this helps
