The European paint systems, like Sikkens, Glassurit and Spies Hecker all have excellent reputations on color integrity.
The original formulation for silver gray metallic, DB180 has been changed over the years, so I have been told by a Glassurit expert.
Also it is very prone to fade, and the early clear coats yellowed with age. It is reare that two DB180 cars side to side match that closely. It is also almost impossible to touch up.
But if it were my money, I'd opt for Glassurit.
Pete Lesler