Yeah the W106 are not working so well on the REAL slick ice, but i avoid doing anything extreme with my commuting bike anyway. If you need more traction (with any tire) just lower the pressure, I have done this with the W106's cause it was just too icy.

Aren't the W240 and 294 new (came out this year?!?) Also for the roads I ride i think the 240 and 294 would be too much resistance for not-needed traction.