We took 2 of these bags camping in 20-30 degree temperatures and were plenty warm when they were zipped together. Zipping them together was easy and they were roomy and comfortable even tossing and turning. I gave it a low workmanship rating only because the zippers of the two bags were about 5 inches different in length, which didn't ultimately affect the functioning of the bags. I have only used them for 3 nights so cannot really comment on durability. The only thing I do not like is the large size of the bag in its stuff sack. Its too large for carry-on or back packing. Zip pocket for watch and separate feet are very nice; and the hood kept me very warm. Overall I am very pleased and would buy again for camping via car.
The day I got the bag it was 20 degrees that night, so I went out side and got in the bag on a pad with no tent (most bags are rated while in a tent) and I proceeded to build up enough warmth that there were no cold spots. I could have slept comfortably all night. My $200 down bag rated for 15 degrees did not do that. Most bags don't live up to their rating. It is roomy, warm and has all the features of an expensive bag..