I think that the complimentary colors are too flashy when it comes to car color schemes. Well, they can work if you do it right. You have to have a perfect balance & consistancy or it just doen't work in my book. I use alot of complimentary colors for the club flyers that I design but they call for flashy attention grabbing colors with big bold words. Still in that case if I don't use balance & consistancy correctly, it just won't work. I think that you should just go with a high contrasting color or something suttle like the polished. Just my opinion. I 'm sure that you will make the right choice because after all, its your taste.