Consider this my welcome post, I found this forum while searching for OEM Speed 3 rims. I'm trying to buy 2 of them for my snow tires, which will be installed at the first threat of a storm. The snow tires ruin my cornering performance, so I put them on as late as possible. I found you only need snow tires on the front, the rear will just follow along with no complaints.
Where are located? If you get below 40 for sustained periods of time I would not recommend leaving the stock tires on the rear. It's not reallly the tread depth or design that is the traction problem in the winter, the tire compound gets so hard in the winter (basically freezes).
So you could be on snowless roads on cold days and you go around a corner and your ass end of the car could slide out because of the stock tires loosing traction.
Just saying I would hate for you to be one of the 5-6 guys that will come on the boards this winter and say they crashed, have stock tires on, and then claim that awd would have made their day better.