Mountain Hardwear Sub Zero Vest

I bought it on sale for 80$, so for a quality down vest, it was pretty cheap. It was much too warm to wear while backpacking in 20º weather with snow on the ground, so I'd say it stands up to the insulation test.

It can be a bit tricky to figure out how to fold it up to fit in the included stuff sack. It's awesome for backpacking! Reinforced shoulders, a stuff sack, and light weight combine to make this the king of backpacking winter vests (on a budget). It kept me warm through the night while wearing it bundled up inside of my 0º synthetic bag in a 3-season tent. Nice even fill, good and thick.

This is warm yet compresses down into a small bag (provided). Arm holes are cut so that you have good movement, but drafts don't get through. Collar is warm and zips up as well. Pockets on front and inside are handy. Looks Nice. Reasonably priced. If you want lighter and don't mind spending another $50 look at the Phantom but I think this is a better value.