Well it snowed in Washington DC on Wednesday, so that I knew that my commute would be icy. My commute is 18 miles each way, with most of it on a bike path, which never gets plowed. The bike path was a combination of bare pavement, packed snow and ice. I am using the 700c Hakkapeliitta W106 35mm on my Lemond Propad.
All I can say is that the Nokian Studded Tires are a great product and made riding on ice quite fun.
I never felt out of control on the ice and just had to be extra careful going around corners. Going in and out ruts was a little bit harder. Another benefit of using these tires on ice, is that you will become a much better bike handler.