Plastic boots have a lot of advantages over leather boots in cold and wet environments. Perhaps the greatest advantage of plastics is that it is possible to dry them out after they get wet. This is not the case with leathers.
Plastic boots are designed to have two parts. There is an internal part, the inner boot, and an external part, the shell. The shell is made of plastic whereas the inner boot is made of a combination of soft materials. One may easily remove the inner boot from the shell in order to dry it out.
There are two ways to dry out inner boots. The first is to simply lay them out in the sun. The second is to place them in the bottom of your sleeping bag at night. Be sure to remove the footbed and to dry this in the sleeping bag separately.
To use a sleeping bag as a drying machine it is important the bag is breathable. If there is any type of GoreTex shell fabric on the outside of the bag, moisture will get stuck inside and the entire sleeping bag will become damp and cold.
One advantage of plastics is that blisters are uncommon. One disadvantage is that another form of discomfort develops for some with about the same frequency as blisters. "Boot-bang" or "shin-bang" commonly results from the constant impact of the shin on the hard plastic boot tongue. This primarily occurs when a climber walks on a long hard-packed trail or on ice for a significant period of time wearing plastics.
As with blisters, the best way to cure boot-bang is to deal with it the moment it appears. It is possible to do this by only tying the boot tightly up to your ankle. The remainder of the boot may remain completely untied if the cuff doesn't get in the way. Sometimes the upper portion of the boot must be tied loosely because the grommets in the cuff can catch and cause one to trip.
Plastic boots are an excellent choice for winter mountaineering, ice climbing, Cascade volcanoes and for expeditionary climbing. When fit and used properly they work extremely well in each of these venues and provide for a great deal of comfort and warmth. Many of our guides use them exclusively on volcanoes and expeditions.
--Jason D. Martin