Here is a "quick a dirty" review of the Dr. Colorchip kit.
Overall I'm happy with the purchase. The system is fairly straightforward to use and simple to use. The color seems to match very well. It's a simple idea and I experienced fairly good results. It probably depends on the color, but the metallic black blended very well. While the results are very much better than simply buying a paint pen at the auto parts store - don't expect perfection. If your ok with a great paint cover that looks good from 2-3 feet away you'll be very happy with the kit. YOU will always know the chips are there - but the kit succeeds in preventing others from seeing them unless they look very closely. Again, if you want perfection, you'll probably need to go to the body shop for a respray.
I took a few photos before and after. Not the best quality (cell phone) but hopefully they give you some idea of what you can expect. Hope this helps.
before
after