I could be wrong, but I think metallic is a different story from pearl in terms of how it sprays. I know I've had metallic cars and didn't have this matching issue as bad.
Metallic is a pain in the ass to match too. The flakes can lay down differently and cause color differences at different angles.
But my point was that the OP was saying he should have picked from the colors that aren't so hard to match, but there aren't other "colors" like that. If any, you only have black as a choice then, and that color has its own challenges to keep looking good.