Yep, you have to remember a GTR is a performance car, people don't buy them to put around under 3,000rpm, people buy them to drive fast, and have fun as with any sports car.
Since your new to imports - don't belive any km readings, 99% of them are wound back, look at wear all over the car. Get a compression and leak down test done on the engine, and get it checked out by someone who knows GTR's back to front.