Oh, I thought you meant upgrade in the near future lol. Can't drive that on your Ps, and even if you have the money it's not like there is an abundance of Z-Tunes around. It wouldn't be right to daily drive a Z-Tune though, even a normal GTR should probably be more of a weekend car.
Some cannons are ok, but some really annoy me. My SSS has a loud exhaust, but it's for a purpose - it's a performance exhaust and i've even tried to make it quieter. Then you see some lancers, excels and civics with cannons that sound quiet at idle and then very loud (and usually not good) at full throttle - just for the sake of being loud.