The only thing to be aware of is that the boots (and I've heard them called both here Mickey and Bunny) are pretty much a vapor barrier, which means that moisture has no where to go. I wear wool socks with them and make sure I have an extra pair or two with me. On the other side, if you get water in them (say overflow) you just dump them out and dry the inside with a towel and you are good to go! I wear them snowshoeing too.

Regarding the mittens, my mother in law ordered a pair for a friend in the DC area with Renalds disorder (may be spelled incorrectly) and the friend was very happy with them.

Good luck!