So in anticipation of another week on the AT, I took advantage of frost warnings to test the Disco to its rating. Setup was my BA CS UL3 on our second floor deck which meant no warmish ground to help, BA Triple core long, wide PAD, and wearing a long sleeve tee shirt, medium weight sweat pants and "insulated" long socks(TOG rated 2.13). Evening started at 48deg and low was only 40 inside the tent.

I was quite warm all night and only if I moved repeatedly into the cooler areas of the bag did I loose the warm glow feeling for a moment. At 40 I could have slept well in my skin only. The shape of the Disco is great for moving around with out loosing your heat or rotating the bag from moving(the liner is quite slippery feeling).

This said, it was not until the morning that I remembered the bag has two heat vent zippers in the chest area...both were still open from a previous use in warm weather. After closing them it took a few minutes before I could say it was definitely warmer and helps explain why my lower body was nearly toasty while the upper was merely warm. With the heavy socks my feet stayed quite warm even when I tried to find cool spots. The toe boxes' extra layer of non down filler works great to prevent heat loss and I never had a chance to test its water proofing.

On the bottom the pad felt neutral- neither warm nor cool, BA rates it R=6.0, 0 degs 4 seasons. Despite the loft being crushed under me, its obvious the bag was insulating me from the pad, which the Jungle bag did not.

The pillow pouch easily accepted two 18x14 polyester fill Field and Stream pillows which at 10oz each might be a bit heavy but rivaled my favorite home pillow with a lot support to keep my head up, my "bad" shoulder actually felt better than normal. My usual is one F&S pillow with my BA Pumphouse slightly inflated. The head hood seems to have just the right amount of fill to keep the noggin warm but not overly much and the drawstring provided the right amount of room for my face. MAJOR props for the extra flap at the top of the bag opening, it sealed up around my neck perfectly without being noticeable and just completed the feeling that no draft could touch me.

For *****s and giggles once it got up to 45 in the morning I tucked the Disco into my Snugpak Jungle bag and it was immediately noticeable warmer...likely too much so. Pretty surprising given the Jungle bag has so little insulation one can not really feel it. The Jungle bag is rated 45* comfort, 36 extreme and I'd say both ratings are borderline based on 30 minutes in it only, I did notice with it the pad felt noticeably warm and think a pad with less R factor might leave one feeling the Jungle bag even more over rated. Based on this test,I'm rating the Jungle bag 55 deg.

Overall I'm very happy with the Disco and for me wont sweat being caught in sub 40* temps without needing extra clothing. I think adding a Costco/Kohls down throw would take it into the twentys comfortably. My one and only criticism is the lack of loops to allow it to be tied to a pad at teh top, the feet have two loops.