I live in north-central Montana and we have snowy and icy road conditions for 5-6 months of the year. I run a spool in the rear and an aussie locker up front. Full on lockers work fine in winter road conditions, you just have to learn how to drive with them. It's true that you can get the rear end out as quick as you want, but when you let off the throttle it snaps you back straight just as fast. In this way you almost have more control on the ice than with an open diff. I find them very predictable. You just have to know what to expect.
It's certainly true that the spool eats tires. My ideal would be a Detroit locker in the rear and another Detroit or an aussie locker up front. We rana full Detroit in a 4runner and I found it very predictable and even easy on tires as long as you drove it right. I have found the aussie locker to be the smoothest of the "lunchbox lockers".
I might maybe consider a Toyota e-locker in the rear since it acts like it's not there when it's off and acts like a spool when it's on. I am still leery of anything you can turn off though. I have been out with lots of guys with the air lockers and have seen them quit locking miles deep into a trail.
My rear spool has treated me well also. Tire wear hasnt even been an issue for me, though I never carry much of a load. Very accurate description of how they behave in the snow/ice. I wouldnt recommend one for a long term daily driver but spools definitely get a bad rap
