When I decided that I was committed to the Mercator I knew that only the platinum watch would suit me. I passed up serveral oppotunities to purchase a gold Mercator because the metal was so important to me. For other watches, however, the choice is much less important, even to the point of irrelevance.
For the Quai de l'Ile, which I suspect Francois is talking about, I would be happy with any variation, though I could see others caring very much about the metal. Am I on target, Francois? :-)