There are tons of comments about the Trekker on WB, but most of them are about initial impressions of and expectations for it and not about any real field experience. Has anyone used it out in the field very much and seen how it really performs? I heard the 2.0 R-value isn't exactly accurate because of the Trekker's insulation system, but I don't know. I'm starting SOBO in a few weeks from Katahdin and I feel like I'll be good at first, but I'm thinking the Trekker may not be warm enough by the time I get to NC/TN/GA. Any opinions on going with the Trekker rather than holding out for the All-Season?