I just completed a new Baby Orca 3/4 IX UQ, so I thought I would explain why they are my favorite. I don't have one... every one I've made has been shipped to someone else! One day soon, I will get my own Baby Orca!
It's got two layers of IX, differentially cut, and a nylon outer cover. The darts are all on the inside, so they help create loft. The InsulTubes Torso Heater is in there as well, providing more loft, as well as another layer of IX under your back side. The Baby Orca weighs about 8.4 oz, with suspension.
Shug has said that if you are a backpacker, you should consider a 3/4 UQ. He uses one in winter, with a CCF pad under his legs. I have always done the opposite, using a PeaPod, a KAQ, and a SnugFit. When I get my own Baby Orca, I will travel much lighter!
Here it is, Why MacEntyre likes the Baby Orca