The GT-R is not 4×4 so if that’s a requirement given you’re in the sticks then a RRS or Quattro is a better bet. I live in a small village (up North) & we had some very bad snow last year. The GT-R ended up stuck in front of my house many times & is next to useless in the snow. Have a Q5 alongside & that was perfect.
As for running costs, you’re probably doing very well with a £1500 insurance quote given your age so i doubt you’d see much less than that. Give Competition Car Insurance (CCI) a call as they are the prefered insurer for GT-R’s. Other costs such as servicing, MPG & tyres are what you’d expect for such a car, however it’s a bit of an annoyance that the service intervals are 6K miles/6mths. Average MPG is high teens/low 20’s depending on your driving mix so on a motorway cruise at around 80mph you’ll easily see 26-27mpg but when you bury the loud pedal you can see the fuel needle move