I lost about 10 studs over the course of the winter. I would rate this as a fail, especially in view of the fact that the traction gains were minimal at best. If there was ice, it might have been different. Again, if you have ag tires, with much deeper tread, you can use longer ones that are probably less likely to pull out. Also, the more expensive carbide studs might well have some kind of improved design to the screws, though I doubt it. I also can't help thinking that the tiny holes left upon removing the studs will allow a small amount of air to get into the treads and hasten their decline over the years. I'll be sticking to just chains on the front tires as long as it works..