I recently received my new Greylock 4 (with 800fp activ-dri) underquilt from JRB and I just had a few questions for you Greylock 4 users out there. What do your Greylock 4's weigh in at? The spec on it was 18oz (actually they listed 17oz on the quilt comparison chart) but mine weighs in at 20.5oz. I don't expect the manufacture's weights to be dead on but I hoped it would be closer than that. Have you had any problems with the lack of draft tubes on this underquilt? It seems like the baffles running perpendicular to the hammock should take care of most of the potential issues, but since it's going to be a while before I'm somewhere cold enough to really put this to the test I'd like your input. Overall I'm really impressed with the quality of materials and construction. Thanks!