Welcome back! They're pretty different driving experiences, having driven regular 350z's, supercharged 350z's and 370z's (both NISMO and standard). The 370z is a lot more refined and definitely feels more modern, less raw but more 'luxury', all down to personal preference. What I will say, is the 370z with a decent exhaust system is a pleasure to downshift in with the synchro rev match feature, it's so effortless without the need for throttle blips - it's pretty addictive Found myself slowing down just to downshift in our 370z demo car with the TORQEN ZORST fitted to it.
Good luck with your new purchase!