yes, I can imagine! My mate had the 440bhp version, same shape as yours. His was running much higher than that though as it had a lot of work done on it. The car was then bought by a modding company in Spain. They flew over to the UK and drove it back to Spain, they must have loved their journey back (must have been expensive though! ).
I agree, the interior was hideous!!
A used Nismo is worth around £800 IIRC and new ones are past the £1000 mark. There is always more than enough demand for Nismo exhausts if you decided to sell.
There are some very nice sounding aftermarket exhausts out there, it just depends on what you're after...plenty of members on here will advise you if/when you decide to change