My brother once had a Porsche 911 Turbo S wrapped in white (it was originally black) - cost him a few grand I think but you would never have known it was originally a black car, they did an amazing job. He wanted to try out a white car without actually buying one.
As for the matte look, he also had at one stage a matte grey M5 - it looked the nuts, but it was an absolute pig to keep clean, and you're constantly having to clean it for eg. bird sh!te as it ruins the paintwork if you don't get it off straight away - personally, I haven't got the time to be that attentive to keeping the bodywork immaculate so I wouldn't bother. Also, I don't really like the matte finish on a GTI, its not the kind of car that can carry off that look.