I've had one of these on all of my cars for about 12 years now.
Lanechanger: LaneChanger I
(the pic is terrible, they don't look that crooked).
I swear by this product, like $7 at PepBoys/AutoZone (a long time ago). Basically this gives you full rear 180 degree view. I dont use any of my other mirrors any more. One glance in this mirror and you can see everything that is going on behind you up and to your peripheral field of vision.
PS: This image shows off what I mean quite well:
http://www.lanechanger.com/images/mirror_028_web.jpg
I havent gotten my hands on the 370Z yet (three more days) and I plan on putting one of these on, immediately. Hope it works, considering how big the C-pillar is in the car, and how small the quarter windows are, not to mention how little visibility there is out of the rear window.