There's not really much more to add that hasn't already been said. It's really just all personal opinions.
Forget N/A power. For the same money as chasing an extra 20hp you can get an FI setup and get 100hp.
If you like the progressive nature and predictability of an N/A then a Supercharger will suit you best. It follows the same Torque/Power curves as the N/A, just higher up the scale. If your gonna keep the stock engine then 400-450hp can be had reliably.
As a ROUGH guide for the more popular S/C -
Stillen supercharger= twin Screw type, mounted ontop of engine, most like an OEM fit (the one Nissan would have used) Sounds the best with a 'mad max' whine, need a after-market bonnet to accommodate, realistic/reliable power= 360 - 380hp.
HKS = Centrifugal type, mounted where air intake is, Mounting bracket quite factory looking, realistic/reliable/reliable power= 380 - 400hp
Vortech = Centrifugal type, Mounted where air intake is, Mounting plate looks a bit DIY, Sounds like a Jet engine with a BOV, realistic/reliable power = 400 - 450hp
If you like excitement/unpredictable-ish sudden boost of power then Turbo is the way to go. I can't tell you much about the different turbo kits for the Zed because I decided on S/C.
Turbos are more exciting than Superchargers because of the massive increase of torque when the boost comes on line and because of that they feel faster even if they only have the same power.
I personally went for the supercharger because I liked the predictability of the linear power curve and because I'd come from 5 years with a Twin Turbo Supra so fancied a change.
In my opinion, the 350z is too slow as an n/a. I'd wanted one for years but every time I test drove one I found it underwhelming and craved for more. It was only after joining this site I read about FI for them and decided that would be the way to go.
After looking into buying an N/a and doing the work myself, one came up for sale that had already been done. I decided to go and look at it/drive it just to see if it was defiantly what I wanted to do. When I saw the receipts for the work carried out I realised that it made much more sense to buy it rather than build it, so I did. Saying that I've still spent ££££'s getting it to how I wanted it.
But I love it !!