Neither myself (Q7) nor my wife (Q5) had to put chains on our 800 + 800 miles round trip Bay Area - Utah - Bay Area. We had some weather other mountains with chain control in effect but since we had M+S tires and 4 wheel drive we were not required to put chains and neither of us felt we had to do it. Overall both cars were stable and while Q5 had a few places where my wife had to slow down significantly, neither of us felt unsafe at any moment. I have z6 in the trunk but based on my experience so far, if I need to put chains on, then I rather find a place to get coffee/lunch/dinner or just stay overnight. Q7 with M+S tires is super stable already and I don’t want to drive in the conditions when I need chains.