I felt the Nismo package was worth it for a few reasons:
I like uncommon cars, and while 370Zs are rare seeing someone with the Nismo setup is basically like seeing Bigfoot... The Nismo body kit also really enhances the look of the 370Z - in my humble opinion.
And I tend to just drive a car, stock, for a year or two after purchase to make sure I know what I want to get out of it and have a solid plan. The Nismo package is about 80% of what the average Joe eventually does to their base-model - so, for me, it's a time and effort savings before getting to the good stuff like forced induction.