William B.wrote a review of MontBell U.L. Super Spiral Hugger #3 Down Sleeping Bag: 30 Degree on October 21, 2011
Setup: So far have used only for 1 trip through the Shenandoah National park, about 6 days hiking the AT. Temps were down to the 30s at night 1 time, but usually 40s. I had a partner to my tent and used a half length pro-lite, as well as a thermal shirt w/ boxers. I'm 5'8" and have a regular length.
Comments: Bag was warm at the temps we experienced, but in the tent it was only about 50 at the coldest. I was very toasty though. The bag does make this ruffling sound when moved (the Pertex material) more than other bags I've had. That didn't bother me after 15 minutes. The materials are very comfortable. It's very spacious.
Cons: Like any 30' down bag, the bottom does compress when lying on it. So, I found that my half length pro-lite was not sufficient to be comfortable. I'd recommend a thicker/bigger pad than that, unless you're a solid sleeper going for ultra-minimal. I'd consider myself a more light-weight guy, and poor sleeper in the backcountry. I think this bag will work, I just need to carry one of my 1lb + pads.
Pros: zipper length (nearly full), ease of moving zipper, warmth, compressible, US company. Big inside.