I think those studs are too far out to the side and there isn't enough of them. You need some more studs closer to the middle of the tire. Yes I know it will increase the rolling resistence but at the same time you will also have a much better traction on ice. Screws are cheap to replace as they wear out. I don't mean to be critical but I just wouldn't trust those on slick ice. I really like the ones I bRAD posted, I made something very similar.