As a fellow Silver Grey roadster owner, here's my opinion:
Maybe not the exact wheel colour in question, but part of me wishes that instead of shadow chrome I went for a shadow bronze. I think it would add a nice touch of colour to the otherwise monochrome Silver Grey. Also note that Silver Grey is a somewhat blue tint of silver, so bronze will contrast nicely with it. The M2 Competition wheels are available in a bronze colour and I reckon it looks great.
Ignore the STI references - the difference between STI gold/bronze and a darker bronze is night and day,
especially if the car isn't blue