I've been using the Luft sweater as a base layer for both commuting and outdoor use, including winter cycling, hiking, snowshoeing, and XC. It handles moisture well, and is a perfect match with a good, breathable shell (I pair mine with an Arc'Teryx Theta AR).
Size UP with this jacket--I cannot emphasize that enough! I bought a medium the first time (my normal size), and could barely zip the coat up. Now I'm in a large, and I love it.
I see other reviewers are mentioning the stitching coming apart and the fill coming out; I have yet to see that happen. If that is the case, you should send it back and get a replacement!
My girlfriend has taken to wearing it under her Triclimate when she walks her dog, because she says it's so warm and comfortable. That's a significant endorsement, because she gets cold when its 70°F outside!