Here is a video with Vitaliy Syulyukov and his friend having a bit of a race between a 2011 Saab 9-3 XWD 2.0T Aero Hirsch with a basic 2008 Saab 9-3 FWD 2.0T sedan.
Vitaliy gotta say it was a pleasure filming thing little video and Credits to hisfriend Dutch for putting it all together and editing. These are two models, the first is the basic LINEAR (Arc) and the Aero XWD with Hirsch accessories, they have the same engines 2.0T with automatic transmissions.
Both Saabs have the same power (at least according to the narrator, i.e., the XWD model is not an additional Hirsch tuned), because of the XWD system the second car is more heavier, but it has reduced slipping:
As you can see, although we do not know what kind of tires they have and what engine condition they are, both cars have similar performances in the acceleration competition. However, the subjective feeling is that the white Saab still provides a better user experience, primarily because of all of these Hirsch accessories and the XWD system.