Having owned, a 2003 350z(DE), 2008 350z(HR), and a 2010 370z... I can tell you there are significant differences between these engines.
2003 VQ35DE had lots of low end power due to the high TQ delivery. The problem with this was that after about 380-400RW HP, the rods would go... pretty weak limits I had a turbonetics turbo-charged one making about 375 RWHP on 9psi... I didn't really beat on it, but it moved well... but the sad part is you had to build the whole engine to move passed this point... and its INSANELY expensive to do so(at least at that time it was). Although I never really beat the crap out of it, I had some nice racing results
the 2008 350z was a significant change in the engine. The car from factory was a freak high revving engine re-designed to make HP with lowering the TQ delivery to reduce engine damage over time, but dam... revving it up to 7500 with no issues felt and sounded amazing. Simple bolt-ons including, headers, exhaust, intake, test pipes, etc and tune put you over 300 whp in no time. Adding a turbokit to this car put you 450-500 WHP no problem with very few issues whatsoever as long as you didn't beat the crap out of it everyday like any modified car.
the 370z engine felt similar to the HR but jus with more HP(332hp). It wasn't a drastic feeling until you revved it up passed 5000 rpms. I had all the bolt-ons on this car with an Osiris flash and I was over 300rw hp no problem. These with turbokits on them with chill at 450 to 550 whp all day long with engine build needed... but the kits are a lot of money... typical Twin turbo kit with all supporting mods before labor costs put you over 10k no problem.