I can't comment on whether 1/4" is warm enough as I have never used a pad that thin. I use either a 3/8 blue foam (doubled) or an older thermarest. 20" wide is not wide enough for me in a hammock if the temps drop below about 50F. My shoulders and sides get cold and I need to use a second, short pad set sideways to wrap around my shoulders and arms.
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If I wouldn't eat it at home, why would I want to eat it on the trail?