Yeah the new hit is scary, and while I love the Z so far. Saying it holds it value better than most, is at best, a laughable statement! The only thing comparable is the rx8, which also seems to be taking a nosedive in used prices.
EDIT: This statement infact was true a few years ago, as I've always monitored 350z prices and it always seemed to hold it's value exceedingly well. Jeeze, I remember just a year or so ago a 2003ish model was the same price as a 2007 is now!
In regards to the Cupra vs Z, which Z do you have, and what's the difference in power like? I'm assuming you just had a remap without additional breathing mods? As power weight doesn't seem very different, seeing as the Cupra is almost 200kg lighter.
Im bloody well hoping it feels a lot more planted that the cupra too, it's a 2 seater sports car after all. I have driven a Z on a brief test drive, and also taken one round a few laps of a track, but these were both a good few years ago, before I had a comparatively powered car of my own, so my memory of it is hazy at best! Ihope it doesnt dissapoint!