Nitrouz,
Good luck with your new 370z once you get it. As Juno stated earlier, we made the switch a little while back and the Z is def more fun at legal speeds.
I do miss the space in the interior of the GTR though, the Z is a bit cramped for me but she fits in it just fine. Then again, I'm a tad bigger than average. So it may be of no consequence to you.
We've got the Nismo and we are super happy with it. Just upgraded the h/u and the nav in the kenwood unit is pretty much OEM quality and fit and finish on the unit is very very good. Since your plans involve so much mods, the Nismo probably doesn't make much sence for you, but if you were to just lightly mod the car, I'd say the Nismo is the perfect platform.
I'm sure you'll enjoy the Z immensely.
