Regarding False Kiva, I hiked it a few weeks ago in the snow. I didn't find it hard, but did wear extra traction and used hiking poles. I don't think it is too difficult, and I am by no means in tip top shape, but it all depends on your experience and capabilities. It's definitely worth the venture. In the winter, the snow and ice can make it slick, but due to the cold and conditions, I also had it to myself for a few hours which was marvelous.