Do the 350Z imports suffer the same problem as the 300ZX imports in that the diff and gearbox cooling isnt upto the european prolonged speeds, I had a problem with a import 300ZX TT in which the auto box seized solid, i was told by a zed expert that the import 300's are dying in droves because of this problem. the uk spec car had what they called the autobahn pack ie uprated cooling.
As I know from bitter experience this can be a very very expensive fact to miss out on.