Dont waste ur money just get a GTR or something when ur off ur P's if u want power its not worth screwing around with N/A cars for power unless u have 15k to throw at them to do it properly and by that i mean rebuild the entire block pistons con rods ect, turbo kits ECU, injec, brake upgrades suspension, transmission/clutch/gearbox upgrades. If you do it half assed u will blow the engine out in around 80,000km from what i have seen on G35 driver, they guys that drop SC and Turbo kits in all blow engines if they dont do internals and with the power u get from doing the internals you will need to do the listed supporting mods or u are going to not be able to stop/damage the car.
I would just keep it as stock as possable then when ur off ur Ps get a 34 GT-T and go nuts with that. If i fit into one thats what i would have done.