Will,
How does PrimaLoft "Sport" do for repeated compressions in a stuff sack? I think it's PrimaLoft's latest iteration.
I have a similar British military inner jacket made with Thermoloft Micro insulation & Pertex which does very well after many compressions.
I ask because my 10 year old Caribou Mountaineering summer sleeping bag with the original PrimaLoft lost virtually ALL its loft after 3 summers, making me very leery of using PrimaLoft again.
Eric