Not sure which stock tires we're talking about... Hanooks or Michelins, but I'd like to add that the stock Michelin Primacy XC's are total garbage in Snow. I live on the benches of the Wasatch Front range at 5000' elevation. We drive up the canyon to ski and visit family in the canyon many times a week through the winter. I have driven many cars and SUV's and this is the worst tire I've personally owned in snow bar none.
All though an All Season tire, it's noted to have "All Terrain Traction" on Michelin's site. We have yet to swap them out, but we no longer drive it in snow. We use our Honda CR-V with Toyo Open Country AT III's instead. The Expedition made one initial run up the canyon in snow for a ski day and it was so bad, my wife could not make a bypass road and had to wait for the main road to open back up. Never again will she drive it in poor conditions unless new true A/T rubber is put on.
Everyone's idea of what a bad snow situation looks like is different and I admit that for us, a bad day is likely heavier than many other's view based on our location. Therefore I would never expect an All Season tire to perform as well as what we need, but I definitely expected more than what these Michelins can give. Sucks to replace rubber with plenty of tread life left so we let it sit on bad days and drive our CR-V for now. True A/T's always go on every vehicle of ours when we do replace tires.