Anyone with experience using vapor barriers? I've found two companies in the U.S. that make VBL clothing. One is Warmlite.com and the other is RBHDesigns.com. They say its the best. People I've talked to and stuff I've read online is a mix of a few people saying it is fantastic (but requires more fuss) and most say it has limited use. Also, I'm not just talking about socks but vbl shirts as well. Personally, I've experimented using bags and raingear with mixed results.
Anybody have experience with VBLs?
Vapor barriers for shoes like ski-boots are good if you plan to stay out for a long time or if its really cold. The shoes won't get wet from the inside and this prevents it from freezing at night so you don't have to have them in your sleeping bag.
plastic bags are fine for this use, but personally i wear the VBL vapor barrier socks, they hold up longer. Make sure to wear a thin base layer sock underneath, preferably wool to better deal with bacteria and smell, and also a thick wool(smart wool heavy mountaineering) or a fiber-fur sock outside the VBL sock to protect it from the shoes and keep your feet warm.
A good alternative might also be a thin neoprene sock, but make sure its roomy since getting wet neoprene over wet feet or wet liner sock can be a drag.
Vapor barrier for sleeping bag or upper body is absolutely not necessary unless you plan to stay in temperatures below -30/-40C for extended periods of time, and this is only for the bag.
For the body it will never be necessary unless you plan to do physical activity in your insulation/down layer. and for this a neoprene vest will be sufficient. altho moving around in down clothing is not something you will need to do if you know how to layer correctly. Except for mountaineering obviously.
2. For light and static activity in subzero (down to say minus 30 or 40), what would you wear over that? (No down, please. When in remote, off grid places for a long time, down is difficult to completely reloft.)
This is just not correct at all. A quality down jacket (RAB, PHD, TNF Himalaya, Bergans Expedition, etc) will have no problem with relofting. Its all about the CUIN/Fill power in the down.
Choose 750 or over for Extreme cold temperatures.
Down is the preferred insulator for all extreme cold expeditions and is also fine for military activity if it is dry-cold or very cold so things don't melt.
for 0 to -15 i would go for a thick primaloft jacket for military activity.
I would also take some of the advice here with a pinch of salt.
Using only wool net, 200g of wool mid layer and a shell jacket as static insulator in below -30C will be at best uncomfortable and at worst unsafe.
If you plan to do this you better make damn sure you have a good sleeping bag to crawl into..
As for the Aclima stuff, their mid layers are of good quality, maybe one of the best..
The Warmwool Hood sweater is a great product since you get neck protection integrated in the top so you don't have "cold-brigdes" at the neck..
I don't know what you are planning to do but if you are ski-trekking or something in temps below -30/-40C (and don't plan to get wet) i would say that choosing something else than down would be the less smart option..