Painting metallics of any color is a very tedious task. You can have a variable from the manufacture. You could also have variables from the place that is mixing your paint. Also how you prep the vehicle and how you spray greatly affects how well it will match. Even raising or lowering air pressure affects how the metallics flow. Mine is very close but not spot on. I originally just wanted to spot in on the fenders but one fender I had to feather to the edge where the door jamb is. Under certain light, you can see a small difference in the hue. When doing something like this, it's best to blend into the next panel and then do a clear overcoat over the entire panel.