I've gone comfortably into the 20's with my 3S Crowsnest (Phoenix), a small foot pad, and an old Camp5 down bag converted to a TQ. I've now got a 3S Burrow and I know it'll beat that old Camp5 converstion. Much better loft and coverage. I'm guessing you had air leakage on the UQ.
UQ's have a learning curve for sure ... but once you get it figured out ... they're great ... and Adam n Jenny makes some of the best IMHO.
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