Prologue: For the last two years, I've only worn Vibrams. Every day. Rain, snow, summer, whatever. Before I wore the vibrams, I was spraining my ankles every couple of months. Now, no sprains in over two years, despite the fact that my ligaments are still too loose and pop out of their groove every so often.
The problem is winter. Before the vibrams, I'd amassed a nice collection of knee-high socks that kept me happily warm. But, they weren't toe socks. Until now, no one made a decent knee-high toe sock. I went ahead and cut the toes out of an old pair of socks just to wear with my vibrams, but that was a little awkward. And my middle toes get cold.
Now, the Injinji socks are not made of wool, so they are likely going to be a disappointment to me in deep snow, and probably freezing rain too. But they've been great in 30-degree weather, matched with my leather Treks. I've gone ahead and ordered two more pairs, despite the fact that they are ridiculously expensive. I can't find them in any local stores.
I wear a womens 9 shoe, and ordered a medium. I don't have any problems with them staying where they should, but I do have very sturdy calves. The compression is noticeable, but not strong. But then, my needs here are pretty minimal- I just want my shins to stay covered.