Steve K.wrote a review of MontBell U.L. Super Spiral Hugger #5 Down Sleeping Bag: 40 Degree on December 17, 2011
There seems to be alot of rookies on this review page.
Your pad factors in, what layers u sleep in make a significant difference.
Do Your Homework.
Ive used this bag in the mid 30s - low 40s with a good pad and a base layer. I was fine.
The bag stretches so being Closter phobic is not an issue, for a Large or XL person this is a big deal.