Besides using the chemicals and Pinlock I also have a snowmoblie visor for my helmet, HJC Symax 3. The snowmoblie visor keeps it clear since it's a duel layer but the extra ventilation on the top can make it a little cold.
Tips for riding in the winter:
1. Never ride when there is a lot of ice on the roads. Not worth it. Just snow it not to bad as long as it's not to much. Anything more then 3 inches on the ground makes it harder to get traction.
2. You need to ride a lot slower especially in the corners.
3. Also remember that you can't stop as quick, just like a car, so increase your following distance.
4. Pay attention to the weather, you don't want to get to work and it snows 12 inches while your there.
5. Layer, layer,layer, you don't want to get to cold while your riding. It makes it harder to use the controls if your to cold.
I only live 2 miles away from work so if I can ride the DT I do. I have enough good cold weather gear that temps mean nothing to me. A lot of snow is another story.