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Advice: Do not get sport package if you use it as commuted car!
My Z4 is a 3.0 model and got fully loaded. It produced plenty of power, but does not corner as well as the 330i or M3. With the sport package, this car is more suitable for weekend driving rather than everyday commute. The head rest is useless and the seat could be more supportive needed when cornering.
Z4 + M3 seats = my best wish :).