SailFree

I just sold my 2004 Infiniti G35x with leather seats, and the interior appears new. I think one reason is that, though I live in Virginia, I avoided sun/heat damage by ALWAYS putting a front window sunscreen in place when parked, even on cloudy days--never know when the sun will come out and bake your vehicle while you are in the workplace, for example.

For the 370Z, with the big rear window in the coupe, it would make sense to shade that too, but quite a bother. I just lay a sunshade on top of the cargo area cover and it raises and lowers itself when I raise the hatch. It doesn't fill the window, but instead of the sun hitting the black cargo cover and heating it, much of the light radiates right back up through the back window.

Keeps the interior noticeably cooler than simply using the front sun screen alone.

For what it's worth...