I hardly post here, I'm more of a silent admirer
But here I can finally help out a bit I think.
The 14-spoke OZ rims were the ones originally designed for the DBR9. They've been on the car since it was introduced. For 2008 the new 15-spoke rims have been introduced, both the factory team as the Gigawave team in FIAGT has started to use them. But because of the large amount of 14-spoke wheels available those are still in rotation, so those are also still used on a frequent base. For the Gulf car I would vote for the 15-spoke rims.