Jim, I just wanted to throw 2 bits in as well. I have a Western Mountaineering Bristlecone MF and a new untested MicroNight Bivy from OR, but the Bristlecone can zip 2 bags together or lay flat like a blanket. I know it's down but it's very versatile. It all depends on what you want. I have a North Face synthetic bag and the WM and I've slept soaking wet in the North Face at 35 degrees and was extremely cold but doable, the mountaineer wouldn't fair in the rain but for the weight and warmth out of the WM bag out weighs my NF bag any day. But it's all in what your mission parameter is, I don't think you can go wrong with either bag, the Wiggy or the WM. The Wiggy bag is really expensive as well and both have lifetime guarantee. When I tried the Bristlecone, due to my size it was a perfect bag for me, roomy, extremely warm, use it as a blanket in warm weather, join it up to another bag for a his/her bag, or unzip the foot box to let my feet air out while I'm buried deep in down. Extremely comfortable and allows you to adjust your temp levels to reduce moisture levels. Just don't add rain storm. Anyway, I think the Wiggy bag will be a good choice for you for wet environments but I just wanted to let you know there are other manufactures with the add a bag zippers.


http://www.westernmountaineering.com/ind...mp;ContentId=40
http://www.outdoorresearch.com/site/micronight_bivy.html