OP - It ain't that simple. What do you want to do? Climb an ice covered hill? The 2 wheel drive, bald tires and chains, hands down. Drive almost anywhere else, the AWD with snow tires. Chains just don't work for normal, day to day travel. And having the back end without chains means you can get going fast enough to have an up close and personal lesson on oversteer.
The real question is not should you have winter tires, it is how far north should you be before you get them. My way of thinking is that if you routinely get snow, you need them. If snow is unusual in your area, no. It't the fuzzy, grey area that is difficult to say. Down here in Alabama, we get snow every couple of years, not a big deal. Everybody just get stuck on the interstates for a day or so. (eek)