[GP20]

I owned an '03 2.5i without the sport package, and made the mistake of not test-driving one with the SP before the purchase. Long story short, I traded it in for an '04 3.0 about a year later. The SP was what got me thinking about the swap in the first place, the bigger engine didn't hurt either.

The sport suspension isn't really a big deal IMO; it isn't that much of an upgrade anyway. You get a slightly lower ride height (about 0.6") from the shorter springs, and sport dampers and thicker sway bars. And for an '04 it won't be long before you need to change dampers so just plan on getting some Koni shocks and either OEM sport springs or Eibach springs. You get different wheels assuming the car still comes with stock wheels.

It's the sport button that really transcends the car and makes it a lot more fun to drive. The sharper throttle response and heavier steering make the car actually drive like a sports car. Without them, the car feels a little soft, and just, not as fun. IMO, the sport button is a must when buying the Z4.