I came into this the wrong way round.
Knew nothing about Zeds until I came here, then fell in love with the 370Z I have as a user
I didn’t really get to drive a 350Z for months later.
I found the two car incredibly different in every way when you get down to it, certainly not just a face lift!
Personally I find the 370Z more up to date fit and finish wise, and the materials of a better quality.
Both have their charm in a similar way to the old and new shape Audi TTs
The original TT seemed streets ahead of its time when it came out, and some of the details kept it interesting over the years i.e. the petrol flap releases and the James Bond wind deflector on the roadster. However when the new TT came out, it made the old shaper instantly old. The new one was more sanitised, and the old one had more originality, but the newer one was a better car, which you would expect from fresher technology.
Bit long winded but that my opinion and it the same as the two Zeds...