Vapor Barriers

I have two hobbies backpacking and deer hunting. I have always been plagued by damp cold feet when sitting out in the woods while hunting. I have tried all sorts of socks and boots to try and minimize the problem. A little bit ago I started to look deeper into VBL'S and see what information there was on them. I came across some good information about how they work on the net and in a few books but have any of you ever used them. I am wondering if there are any caveats when using them or if they are really worth using. In theory they sound like they would solve my cold feet problem when hunting but how do they work for backpacking? Any advice would be great!