Down shift can be an advantage in a hammock quilt i.e. the HG, you can shake the loft to the top of the quilt where it does the most good.
Keep in mind that staying warm is about more than just the insulation; proper UQ adjustment, eating before bedtime, head coverings, loose fitting socks, etc., etc. all contribute quite a bit.
I'm sure either will make an excellent quilt for you, just mind the small details as well.
David
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