Left my 350z with Nissan yesterday and they said if the fault is wear and tear on the clutch then the £322 to remove and refit the gearbox would be billed to me and also what ever clutch work that needs doing. I am not happy about this as i've now only done 12,000 miles and still with a warranty, do they think i take it out on track days or what? I then tell Nissan this clutch issue is well known for the 350z and he says in 6 years only 2 350z's have come back with clutch issues. Well that's probably because 350z owners go where it's cheaper after their warranty has ran out. Time will tell!
I've bought brand new cars before from Vauxhall and Bmw and they have never questioned any issues with a warranty.
On a better note at the dealer i saw my first 370z in the flesh (in white), it looks really nice, so much better than pictures you see in magazines.