I agree with the OP as well, wonderful idea! So long as it too had a good preview of your car with the new paint.
But to share my 2 cents worth, the best way to "fix" the painting of cars in GT5, is have a proper preview of the color you select on the car you're painting. Not that useless preview model they show you now. The preview now is not at all accurate to how it will look on your car, its not even the same shade/color!!!! Plus, sometimes it doesn't even paint the whole car, so we have no way of knowing what to expect when we paint cars...
Its really just like Russian roulette, pick a color, cross your fingers and hope it looks good! if not, use another chip and try again!