I agree with Ekona. Its different to a Z but also very comparable. 
  
I feel the Z is too heavy, so is the M3. 
The 50's brakes overheat far too quickly, so does the M3. 
Both are 10+ years old now so inside it a bit dated. 
  
The M3 is quicker in a straight line but not enough just to move because of that. It does have 4 seats though if that's a plus?!