This is the first down bag that I have owned, and it is a sweet one! Off the recommendation from backpacker magazine I decided to buy it because of it's supreme waterproofing. I threw a handful of water on top of it after receiving it and let it sit for 10 minutes. Not even a drop of water soaked in! I was amazed! It is so lightweight that sometimes I feel like I might break the thing, but it keeps surprising me with it's durability. I do find several feathers that clinched their freedom in my tent, but there were no more than I could count on my two hands so it is nothing to worry about.
I decided to use a liner with it mostly because I want to take good care of it, and also because I sleep very very warm. I got into the sleeping bag in my basement after receiving it and started sweating about 5 minutes later, so there is no doubt in my mind that it will keep me very warm during a cold night. My bigger problem with it was that my sweating body stuck to the material of the bag and made it somewhat unpleasant. The sleeping bag liner cleared this up quite nicely though, and I have never slept better in any other sleeping bag than this one! Also, the liner seemed to help wick my body heat and keep my dry but warm, a very important thing in cold temps. I am planning on using this bag to go backpacking in Colorado and the Badlands in South Dakota this fall and I couldn't be happier with my purchase.