I wear the ru outside boots with the removable liners (sz 6....I wear a ladies 7).
Tried the klims but they we just not as comfy as the ru outside boots for my feet. I have slim feet and really high arches. I wear one pair of socks. My feet always get cold but I don't have much of a problem with these boots.
You can also get extra liners to switch out if you get them wet. Only time I used them was when I wore pants without gaters and filled the boots with snow.
I have been wearing RUOutside boots for about 5 years now. They are lightweight, breath well, and keep my feet warm. Last year I upgraded to their latest model, which is like a snowboarding boot. I can't believe how light they are!