GW Matte is NOT a true matte...
... it will give you more of a semigloss finish. Some options in order to deal with this are:
seal x2 with another true matte after the GW matte. If use dullcote, lusterless flat, etc., make SURE the first coat is dry and on the way to being cured (wait a day or two...), or you\'ll end up with a chemical reaction that will turn your GW matte purple, or vice versa.
Seal it with a true matte: floquil, testors dullcote/lusterless flat, and others are truely matte finishes.
And, BTW, I have \'drenched\' jobs that I\'ve done, either by testing the matteness of projects, or by virtue of other people requesting thick sealed coats for protecting purposes. I have putting on multiple coats, and true mattes are still about as dull as it gets. I mean, no shine. Wet when the go on, dull as dull when they dry.
Just a note: when you use a true dull matte, your colors will be toned down. You will need to get used to building in a bit of extra \'highlight\' into your minis. Otherwise, you will run into some problems with them dulling down subtle highlights. Alas, a downfall of the matte.
Also: another painting tip: I usually will seal important steps midway in the process of painting, so I don\'t continually rub paint off, etc., if I need to handle the minis. (Again, another painting technique I should write a little article on, b/c this is a great technique to use, and I\'ve had some really good success implementing it.)
Good luck!