I know folks who hike in Tevas or Chacos.
I can't do it. Not because of the sole being inadequate - I cannot stand having to stop every few minutes to get twigs, rocks, bark, etc. out from under my socks, and cannot seem to walk ten feet without stubbing all my toes on something.
If I were you I would get a cheap pair of Tevas from Sierra Trading Post and walk around town for a while before committing to using sandals on a long distance trip. There are sandals with toe guards, true, but I find that stuff gets in anywhere it can, and stick to trail shoes.
Cold is going to be another issue. Those places you mention are going to be really cold in January. Get your socks wet and walk around in the cold and there's the potential for frostbite/hypothermia.
That was more or less the idea - I am getting them now to give me a couple weeks to walk around in them combined with various sock combinations (it's colder at night here right now than I expect to see at any point on my trip, based on average and record temps spot checked along the winter part of my route). Whatever I wind up buying will be what I wear for the trip though, *if* I decide to go with sandals. I am going to get a pair of good walking shoes too, and test them the same way. The winner gets to be walked to death :: grin ::