Not to resurrect a dead thread - but I wanted to share my experience with KO2's in the snow vs. actual snow tires.
I put KO2s on my '95 80-series. My wife has a Sequoia with that we put Blizzaks DM-V2s on in the winter, since we live in North Idaho and do quite a bit of winter road-tripping in her car.
The KO2s are far better in the snow than any other A/T tire I've ever driven. Fine for getting around town, and predictable on anything this side of sheet ice. But the Blizzaks are night and day better in the snow.
One week in January we were both coming back to our house from town during a freezing rain, which was falling on top of snow. The slickest roads we've had all year. The first 100' of our gravel driveway is pretty steep, steep enough that FWD cars have a bit of trouble sometimes even during the summer.
My wife went first, and just drove straight up it in her Blizzaks. I watched her tires spin just a touch at the very top, and thought "oh, maybe it's not so bad."
I made sure I had some momentum, and went for it. About 3/4 up, I totally lost traction and ended up sliding down backwards. I tried 3 more times and even did a 180 sliding down backwards on a couple tries.
Finally, I remembered that I was in a Land Cruiser, put it in 4low and locked both my diffs, and barely made it up on the 4th try.
When I got up to the house, my wife who'd had no trouble at all asked, "what took you so long?"
The KO2s are a great tire, and if you only get occasional snow or don't do any road-tripping or highway driving during the winter, you could definitely keep them on for 4-seasons. But if you're planning to do a significant amount of highway winter driving, I'd invest in a pair of actual, dedicated snow tires.