Had them on for a while, but only using it when conditions call for it. Today, for example, I left the house thinking everything was good to go with the 25 mm slicks. There was a light dusting of snow on the road. I probably still could have ridden on those tires but didn't want to take the chance. Who knows what that dusting is covering. So when in doubt I err on the side of caution.

When I run early in the morning that light dusting of snow is the most treacherous because you can see what it's hiding, and often times it's a puddle that froze over night. I've fallen a few times over the years by stepping on just that.