My Western Mountaineering Ultralite also has open baffles, and the down does migrate. Some people (evidently the kind who stay in one place all night) like this feature so they can shove most of the down to the upper side. I change positions, usually from one side to the other, every hour or so at night, so I really need the down even on all sides. I've found that I need to redistribute the down almost daily during trips. I'm therefore sending my bag off for an overfill this winter. The additional 2 ounces will be worth it, IMHO, and keep me warmer to boot. BTW, the current price for overfill for the Ultralite is more like $20.00 plus shipping both ways for 2 ounces.

Rionada,

My experience is just the opposite of yours...I think. My Feathered Friends Swallow bag works great as an unzipped quilt but doesn't do as well as a zipped up sleeping bag. Go figure?

The Swallow has continuous baffles and I had it overstuffed with 2 ounces of down. The down stays evenly distributed when the bag is lying over me like a quilt. When I zip things up (sleeping bag mode), however, the down migrates. As I turn back and forth during the night I evidently massage the down in a way that moves it to the sides within a few hours.

I think my bag is too narrow for me and here's my current guess as to why the down does or does not shift. When the bag is lying loosely on top of me (quilt mode) I can spin to my hearts content without rubbing the bag and moving the down. When the bag is in sleeping bag mode it is tight on me (think burrito) and I press outward against the inner bag every time I move.



This whole sleeping bag warmth thing is complicated and confusing........and interesting.