I have the Wiggy's Antarctic and I don't think it is a -60F bag. However, two things: 1. I sleep really cold and 2. I didn't know there was a second around the body tighen down "strap" and was using woolsocks to make a kind of draft tube around me. He doesn't believe in an insulated draft tube below the head area, but he did put in a tightener. I was on the trip for almost three weeks and never noticed. AARG.

Another note - I took this bag on my last winter overnight and we (I was not driving) crashed into a ditch on the way there. So in the chaos I didn't notice my sleeping bag had gotten wet from an exploding water canister. It was about 0 - 15F that night and while I was chilly, I wasn't hypothermic.

Another thing - the bag is FREEKEN huge - like no room for anything else in my backpack huge.

(oh and on a side note for those of you who remember the whole is could my feather alergic husband handle a feather sleeping bag - he slept under a high end down blanket at his parents and was miserable. I checked after the second night (the first night he told me he was sure it wasn't down) and it was down. He got better the third night after I kicked the blanket out - so I made the right decision for us, I think. (no feather sleeping bags ) )