I have 17" Santa Monica's (V6 4motion) but didn't go with the diamond cutting as it costs £150 per wheel and they need your wheels for 10 days!! Also, because of the finish, i.e. lacquering over a polished surface in effect, they couldn't really give a life span... basically if you kerb a wheel or get a scratch that goes right thru the lacquer you're back to square on again so felt it wasn't worth the risk for the money?
They do have various paint finishes that mimic the finish you're after which is what I went for, I really wanted to stay totally original but went for 'black chrome' which looks really good against the metallic british racing green of the car!