Gary Novack wrote a review of Marmot Pinnacle Sleeping Bag: 15 Degree Down on August 17, 2010
I just tried a new Pinnacle on a backpacking trip in the Sierras. Minimal temperatures were probably upper 30's to low 40's. Altitude from 7500 to 8900 feet. I used a tent, thermarest and groundcloth. Previously, I had been cold in a 15-year old REI bag of similar down weight. With this new Pinnacle, it was great. I did not have to zip it all the way up, and did not have to use a sleeping bag liner to keep warm. I highly recommend.