For some people OEM parts will always be the preference for their restoration, regardless of cost.
I suppose it all comes down to just how "Original" is an Original or Concourse restoration and how much are you willing to spend ?
A friend of mine has just spent a serious (read large) pile of money doing a concourse restoration of a Series I E Type Jag. A large amount of the money went on securing Original parts regardless of cost.
Oh, to have the money