I ride in an area with ploughed roads and dont travel too far during the winter (<5km).
I have ridden a number of winters with semi-deflated knobby tires and slip at times (usually too much snow) but never noticed ice. Those commutes were primarily on side streets though.
Now im in a new city, and my commute is on streets with heavy 60km/hr traffic. Would you feel that getting studded tires would be an increase in my bike happiness (couldnt figure out how to word that).
Im a little hesitant to be in these high traffic streets.