LHCwrote a review of The North Face Dolomite Double 3S Bx Sleeping Bag: 20 Degree on September 25, 2013
Familiarity: I've used it several times
This bag is great for car camping. Plenty to room for two and great design with easy access on both sides of the bag. Really comfortable down to about 30 degrees or so. Not sure if it would make it all the way down to 20 degrees without some help, but I can't really confirm because I've never used it below the mid thirties.
Weight of the bag is reasonable at 6 pounds, but might not be compressable enough to take backpacking, unless you've got a fairly large backpack.
All in all, a superb product that's affordable and does what it was designed to do very well.