I strongly suggest that buyers who wish to suffer less or potential buyer's remorse please review the Owner's Manual located here by AK370Z:
370Z Owner's Manual
I can say that we purchased the Touring package without the nav, and I like the center console better for its styling, but the Owner's Manual really caters to those who buy the nav package, and sucks when it comes to the other choices. The nav unit also has some of the car's features that can be adjusted on-screen: p. 4-6 (p. 129 if you input a page).