Providing that the car is in great shape, only 6mt 370Z's will be classics.
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Of course auto's will still be a classic, just not as desired.
Here's why, in 20-30 years there will be no mass produced 3 pedal manual trans cars made, plus the Z34 was the 1st 3 pedal manual trans car with SRM. Also this will be the last Z to use Nissan's famous naturally aspirated VQ engine and if that's not a classic, I don't know what is.