I don?t think there?s an aerodynamic advantage to matte or satin finish. All three finishes protect the underlying surface. The only question that is relevant after that, is ?what do you like?? I think if you are trying to sneak in low behind enemy lines without being shot down, then a camouflage matte finish is great idea. And it looks cool at flyins and such. But for me, I prefer a shiny finish on my pride and joy. It?s why they make chocolate, strawberry, and vanilla - do what makes you happy. I just picked up my new RV8 from GLO today and its pretty shiny...... I?d say it?s my prettiest one so far - out of 4 RV?s. Some people might not like a pretty shiny airplane, but I don?t care, and neither should you. If you like the satin or matte look, I say go for it. In the unlikely event that through some aerodynamic anomaly it makes your airplane faster, I think the difference would be so small that it wouldn?t be measurable. So the reason for your choice should probably be a personal aesthetic preference.