I previously owned a 2000 M Roadster. Loved the car - a beast. Tight handling, throaty exhaust, a rocket launcher. My buddy owns a 2002 330Ci - refined car, snappy, loved the top. I thought the 2003 M3 w/SMG would marry the best of both. It does - in a way - but after owning it, I still find myself longing for the purity of the M Roadster. It's just as fast (01-02's would actually smoke the E46 M3), handles better, and it's way lighter. The M3 outputs 333HP but it weighs 3780lb. The SMG trans screams at high RPM/track driving, but it takes getting used to around town. For an awesome daily driver for the fam, save the $ and get the 330Ci & buy the M Roadster for the weekend.
SMG (for race/track driving only, though), Sport mode, HP, excellent handling for the weight, good DSC, power top, 19"s, hard top (improves chassis rigidity) overall appearance, love/hate relationship w/the the back seats for practicality/performance reasons.
The exhaust note stinks. C'mon, for 333HP and this kind of $, I want to be reassured of my purchase every time I step on the gas. The car could go on a 400 - 600lb diet, or beef up with more HP - new vettes and 911's will still smoke ya, along w/majorly modified tuners - the M3 is not invincible.