Originally Posted by TheStigsTwin
It's true, the xi is faster off the line and handles the track better. Otherwise, the i is superior.
why do you think Car and Driver tested 335i (not 335xi) vs S4 ? They said that 335i is a better choice for track because it handles better
XI is a safety feature not performance in ANY way. It can launch faster in less then ideal conditions, its safer in snow (if both have winter tires), and its better and safer in rain. < and all that is not because its AWD, but because 335i doesnt have LSD (which was left out for marketing reasons)
edit: 335i with LSD will leave xi in dust in all conditions