I have two winter boot systems - a VBL and a totally breathable system. (we hike on extended trips with no re-supply or big fires)
VBL - insulated neos with extended gaiter, neos insole, 3 sock system - liner/vbl/knee high wader sock. this works well for high energy snow shoeing, but you need to exchange the liner sock after a day or two - which exposes the skin to the cold. (plus the VBL stink factor)
Breathable - custom mukluk with breathable nylon shell, 2-nested felt liners, felt insole, frost plug, liner sock/wool sock. Pull the shell off at night and sleep in the liners. This has worked so well that the neos are now my emergency backup and I keep them in the truck.