Kee surfing. I found a few home videos made in Eastern Europe where a couple X5's are on snow-covered mountain roads. They try to get them to lose control & have to go to EXTREMEs to do it.
On that note, after driving in 4 distinct seasons for 40yrs in many vehicles, This "X- machine" is far & away the most sure-footed automobile I have ever driven on any road, pavement or gravel, dry or snow. When my wife wants to travel over the Mountains in the winter, she takes my X5 & leaves the Explorer in the driveway.
END of STORY.