This bag is in my pack year round. In the winter it keeps you warm and toasty and in the summer I sleep on top for a very comfortable outing without the need for another bag. Plus if the temp drops at night you can always slip inside. This is the only bag I have found that comfortably fits big guys. Definitely get the air pad and pillow to go with it and pick up a compression sack to get the packed size down. Its bulky even when compressed but you won't regret it!
I've been using this bag with the BA sleep system for two wintyers now and it has yet to let me down. I've used it in temps down to -10 and, while I did need to put on a few extra layers, this bag kept me toasty and comfy. The extra room is a big plus too. On the down side, it is a bit bulky and heavy, so if you're an UL camper, this may not be the bag for you. Also, I'd really like to see BA use a liner material other than cotton, for all the obvious reasons (dries slow, is cold when wet)
"Great, roomy bag for a restless sleeper- will get you to 0 degrees no problem."
Great bag! Used it with an Exped Synmat down to -2 degrees w/o getting chilled. My son had my -20 Elk Park bag (sneaky little scuzzbucket), so I got to test the extremes of this bag. These bags are well worth the expense/space/weight of the needed pad. My wife hates the fact that I sleep with "Big Agnes" when I'm camping without her! She wants the company to change their name!!!