If you are interested in buying K/Mouse/Bunny boots:
* Make sure you get US or Canadian military surplus (there are inferior imitations...)
* Wear a high wool sock. It needs to go above the top of the boot--otherwise the rubber will rub your skin raw.
* Most K-boots are very hard to get into--you basically try to use the smallest boot that you can get into. Once you get your foot in, it should fit reasonably well--so use the smallest that does both. Sizing varies according to the source. (When camping, the struggle to get into your boots can warm you up in the morning...
)
They don't have much support--I don't think I could get an insole in mine.
Fitting crampons to K-boots is difficult--only a few brands will fit adequately. And watch out for the upper portions--they can rub holes in the boot. (The integrity of the rubber is vital to their performance.) I put tape on mine to protect wear points.
The soles are flexible--you may feel rocks and crampons through them. They also aren't very good for kicking steps (too flexible--you can bruise your toes). However, they work very well on snowshoes. And you can walk through streams without a second thought...
Expect your feet to be warm, very damp, and very smelly by the end of the day... (If you are multi-day camping, change into dry socks at the end of the day to prevent trench foot.)
BTW, I bought and used K-boots in the mid-1970s. It is possible that the design of boots has been changed since then.
FWIW, a friend of mine still uses hers now and then. (She tends to have cold feet if she uses other boots.)
Doug