I have an 07'323i it's a great car after some mods and suspension upgrade. The power is enough to get around. You won't be disappointed.
Make sure you get the 2007 323i NOT the 2006 323i.
The 2007 323i has a third stage intake manifold which is not found in the 2006 model (hence the 200hp in the 2007 models), and the transmission in the 07 is a ZF.
After some small ecu tuning, the car is on par with the 328i performance.