I just had my first service over the weekend. When I called to schedule I confirmed that they were using the ester oil and confirmed again when I got to the dealership on Saturday morning. Of course the entire first service was free.
I do have "free" service for my first year. I pay for the oil and they do the work.
My GF drives a Mercedes, so I don't mind the service cost on the Z at all. Routine maintenance on her car is pretty pricey.