Ester oil is not full synthetic, it is also recommended but not mandatory for the 370z. I personally use mobil 1. There are plenty of threads on this forum where this issue has been discussed.
Just take a look at some of these:
Esther Oil?
DIY: Nissan 370Z Oil change (AK370Z way) Pictures inside
oil change price... it's like, WOW!
Ester oil or other synthetic? how often?
and there are plenty more if you use the search