I stayed in a debris hut at TB's "back to back" for 2 weeks this past year when hurricane Bertha came through. I admit I had 1 small drip which was quickly and easily patched. Temperatures were not very cold, but the hut was very comfortable. Careful smudging helps to eliminate the presence of any previous residents. I used the layering technique. Total construction time was only a couple of hours 2-3. In other circumstances where I would not be out long, or the weather fair, I doubt I would build one (applying the conservation of energy principle. I would seek alternative shelter suited to the terrain. Don't get me wrong, if I could be out for more than a day or 2, and the conditions were right (no snow here in Texas to deal with) then this would be my shelter of choice.
When teaching survival skills for the general public, I teach the debris hut as primary. It does a couple of important things for a "lost" person.
Eddit Starnater