RED or any other colour is a piece of piss to match if you know what you are doing.
The worst thing is it will not stay matched as paint fades at different rates, and on different areas of car as more areas are subject to sunlight than others, reds tend tio LOOK worse as most have PINK primers.
I had the front end of my car painted, just wings and bonnet, paint was redyed until the painter was happy, panels test painted and left to dry first so mix could be accurately assesed, he is insurance approved, and has a lot of exotic cars to do paint on, and bodywork, but not cheap.
The paint I and he uses is £90 a litre, but you get what you pay for.
tabetha