STi is the best out of those choices for fastest out the dealership, and they sound nice with the right exhaust.
S2000 is small and I like having space.
350Z I would rock one, but G35 coupe 6-speed > 350Z in luxery and looks IMO.
Test drive all the cars and make your choice.
Evos are nice too, you may want to look into that and compare to the STi.
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