I'll take american muscle. No need for premium octane, you can get more options for your money, and I don't have to be lobbed off at the kneecaps to fit into 99% of American Cars.
I've sat in Accords, Civics, Mazda 626's, and a Nissan Maxima, and I could not comfortably fit my knees under the steering wheel.
[edit]Add subaru outback legacy to the list of cars that I can't fit in.
I know it's not engine related, but it is very important in choosing a car
[edit #2] I'll take German, thank you. Nice combination of sofistication, handling, and cabin comfort.