In my honest opinion I don't think the 6 can pull off any colors other than stock UNLESS it has a bodykit... Hear me out before you guys bust my ballz... I'm not saying this just because I have it...I don't know how to explain this with out hurting anyones feelings... So here goes... It's just that 6 looks too bland in stock form to be able to sport an unusual color... Kinda like say a stock Honda Civic wouldn't be able to pull off a matte black because like Joe says it's gonna essentially look like it's primered, but if said Civic had a body kit with aggressive looks it could pull off mostly any unusual color like let's just say booger green for example.
I know you have your heart set on this so if you do decide to do this I would make sure I have the funds to re-paint it I wasn't happy with the outcome.