I used to live in Albany and had the PS A/S on my M3. They worked quite well in light to medium snow. If you live in areas where the roads and consistently plowed, the A/S are a good compromise between performance and grip in snow.
Of course, it is a compromise. Don't expect the grip of summer tires and the traction of full blown snow tires.
2011 E92 M3 DCT
1991 Spec Miata
2008 E92 M3 DCT - KW Competition 2-way / Brembo 365 BBK / OMP ARS racing seats / rear seats delete / GT4 aero / AiM EVO4 data logger / SmartyCam racing camera
2008 E92 M3 6MT
2008 E92 335xi