The MSport and the 323i is a totally different car when it comes to pick up, top speed and most obvious would be the handling, not to mention the full MSport trim which includes a thicker steering and air cushion waist support. Of course, both also no active steering.. :4: MSport no active steering because to make the car more feel while the 323i no active steering because cut cost.. :4:
Comparing the LCI and Pre-LCI, more than apart from the head and tail lights, and the gearbox, iDrive, all other components are identical.
MSport is purpose built for hardcore rempit kaki while the 323i are for the Merc convert i.e. emphasize on luxury and comfort, not handling. Which one is you?!