I have RWD with winter tires. *Touch wood* never got stuck once. Never slid down a black iced slope either. Almost nothing climbs a perfectly flat and black iced slope tho. Accl and brakes faster than most 4WD trucks.
4WD is the biggest false sense of security that put a lot of people in harms way. Keep on hearing people how they have 4WD and still got stuck/slide/crash... well, cuz 4WD doesn't help sh_t. Winter tires is the biggest difference maker! Of course, and also to drive reasonably for the condition.
i used FWD on real snow+ice tire in Prince George's winter...it was perfectly fine
in PG, the police's crown victoria (RWD) uses winter tire without chain(not sure is it studded though)...no need for AWD/4WD, unless driving through somewhere that's never been plowed before.