I'll chime in with some real world experience.
I'm currently 1.5 inches lower than stock (as measured from ground to top of fender arches and compared to measurements provided by Nissan).
19x9.5 +23 275/35 front
19x10.5 +22 305/30 rear
OEM alignment all the way around (camber, caster, toe, etc.)
Yesterday, I found out (the hard way mind you) that the front does NOT work. Hit a pothole and my front tire made sweet love to my fenders, which are rolled/slightly pulled too.
Take a look at this thread for your reference:
http://www.the370z.com/wheels-tires/...pecs-only.html
Hit me up if you need more information! You're welcome to stop by and check out the car if you'd like.