Interesting post - thanks for the info. I mainly use the same tire in winter too. Probably have 4-5000 miles on these tires. Like the other commenter, I've never had a flat (and I commute through manhattan). You probably could have avoided your flat tires if you had replaced the tires earlier. I retired one of these tires at about 3k miles - the center block tread was almost worn flat in the middle of the tire and the studs had become a bit rounded. Stud to rubber wear is about even. Sidewalls casing and rubber were fine as these tires had only 1 1/2 seasons use. I could have used them a bit more (with some performance diminishment) but got some good deals on tires so replaced them early. Last spring I was able to find a few of these for between 30 and 40 dollars on eBay and amazon. Am set for a few years now.