Having driven in snow every winter for over 20 years, I find it surprising some of the things being said about winter tires.
Given same tires, an AWD vehicle can't stop any faster than a 2WD vehicle. It also can't turn any safer in coasting / no throttle maneuver. The stopping distance for a dedicated winter tire are 25% shorter than your typical all-season, and 50% shorter for a studded tire. Likewise, speeds at which turns can be made without loosing grip are higher.
Everyone pretty much accepts that the "all season M+S" tire rating didn't mean much anyways. North America has always been behind when it came to winter tire ratings. Now there is a more recent rating for severe snow, which has the "Mountain / Snowflake" symbol on it.
When roads are restricted due to snow on Alberta and BC highways, they are looking to see if you have the severe snow tire rating, not if you have a Subaru or not.
The people saying "you shouldn't be driving so fast that you need snow tires" are missing the point. The point is road conditions and traffic are unpredictable, especially in the mountains, where all it takes is a oncoming car to swerve into your lane, or a deer or elk to bound across the road, to cause a severe accident or worse. You can never predict what other drivers or wildlife are going to do.
Same could be said for insurance. You're all driving with insurance (I hope) and nobody says "Well you shouldn't be driving in a manner that requires you to have insurance". That's exactly what snow tires are, insurance. Overkill? I'd rather have overkill on the car than someone needlessly killed because they weren't willing to buy snow tire "insurance".
Nobody is saying buying insurance or snow tires is license to drive like an idiot. But just because you drive safe doesn't mean you don't need insurance.
Not wanting to have to change tires for winter is understandable. For myself, I keep a second set of wheels already mounted with winter tires which makes it more convenient. And I always keep a set of tire chains in the car.
But for people who insist on not changing tires for winter, there are high milage "4 season" tires that have the M+S and severe snow Mountain / Snowflake ratings as well, like the Nokian WR.
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