[2K10E92]

EXACTLY. XI is inclement weather aid while Quattro is a performance tool.

That's easy. xdrive is electronic, quattro is mechanical.

A4s lack lsd ( at least until 2010), s4 and rs4 have and had lsd for a long time (or always)

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

Let me be clear. BMW did not design the xi with dry road performance in mind, like Audi and Mitsubishi did. One only needs to look at the springs to confirm this. I'll shut up now.

Originally Posted by Leaker

As I have said before....to quote Bimmer Magazine.... xi is an inclement weather aid while Audi's Quattro is a performance tool.
It all has to do with how power is distributed . x drive is not available with sport suspension or 19" wheels either.

I was wondering if any of you caught the story on the front page about xDrive. It's a good read.

http://www.e90post.com/forums/showthread.php?t=445487

And I understand the source of this article and all, however, it does contain a good number of facts and a number of people on here seem to rely on "just check BMW's website" and "I tend to believe what professionals tell me as they're, well, professionals (C&D article, etc)" as their evidence that xDrive provides no performance enhancements and just plain sucks.