Thank you to all for your comments>>they express both points of view. As I'm not an audiophile, I think that the BOSE audio would be fine sound-wise; I have a 300ZX TT with the BOSE system and works well enough for my needs. However, as I plan to keep my car for a very long time, and considering that the factory Nav will most likely be outdated in a few years + the risk of expensive repairs, I believe that it's best to keep my options open and just install an aftermarket Nav system. This way, I can have the flexibility of choosing the latest technology at a reasonable cost, which would not be the case with the factory Nav.
No doubt, the factory Navigation is the best option to enhance the 370z's interior design, but from a financial and tech point of view, I believe that the aftermarket Nav is the way to go if one plans to keep the car for a long time.
