Originally Posted by markinva
what about he 100% increase in traction that xdrive offers. That's also quantifiable.
Traction depends just as much on conditions and tire selections as it does the number of drive wheels. Your 100% increase, which I'm assuming you arrived at by simply calculating the percent change from 2 to 4 drive wheels, is correctly stated as just that - the xDrive has a 100% increase in the number of drive wheels. This says nothing about how it this increase in the number of drive wheels translates into the cars ability to change direction.
Handling is not simply a case of more grip or higher speed is better. A faster lap time does not mean a car handles better. It means it sustains a higher average speed around that particular track. Handling is very much about how a car does something rather than how quickly it does something. I chose weight figures because they are hard figures and are commonly accepted indicators to the desirability of a particular cars handling.