M5 + winter tires are fine up to around 15cm -20cm of snow of local roads & highway, but the traction control will kick in very often to get a better grip of the roadway condition. I do find a bit tricky if the car is started off on an inclined hill under the mentioned condition but this is not a total surprise to me at all to any RWD car, I supposed.
I have Michelin PA4 19" square setup
|