I've been driving on snowy roads for quite a while now. Normally packed down snow. A week ago I drove out to my buddies cabin on 2' of snow and ended up being the only vehicle that made it all the way out. I spent the night and woke up to another feet of snow, and ended up getting stuck up to the axles while trying to turn around. I have never aired down my tires in the past, but after shoveling for 45 minutes and not getting any more traction, I aired from 35 down to 20 psi and was able to crawl out. At the time I was nervous about even going that low since I didn't have an air compressor and would have to drive 5 miles on plowed pavement after I was out of the woods before I would get to a gas station. After reading through this thread, I'm going to try to go down to 10 psi in the future after I purchase a portable air compressor. Any lower than 10 psi without beadlocks makes me nervous. I'm going to do some more research on how to re-set a bead just in case. There are usually youtube videos for everything.
I have never used chains, don't think they're necessary for the majority of situations if you have a good tire. In regards to earlier posts about studs being outdated... I disagree. My friend that lives in the cabin in an area that averages 400" of snowfall a year drives a Subaru impreza with studded Nokians. The paved road is somewhat plowed, once in a while, and can freeze and refreeze and get pretty icy. He likes to drive up to the gate, which is downhill, at a decent speed, hit the brakes, and stop just short of the gate. It always worries me when I'm in the passenger seat but he hasn't hit that gate yet so I'd say those snow tires and studs work pretty well on ice...
That being said, I plan on purchasing a set of Firestone Winterforce tires in 285/75r16 for my truck next year. Don't think I'll be getting them studded or trying to stop as close to the gate as possible. I had a set of the Winterforce on my own Subaru I owned before my Tundra that were also not studded and they were killer tires.