I live in south Texas where it does get cold, but usually not unbearably so. But I've already had a few days chilly enough to justify the jacket and it works like a champ. It is also very comfortable. The reversible function is great.
I originally ordered an XL, but that seemed a little snug and short in the arms. Duck Camp makes exchanges super easy and fast. Took less than a week for the replacement jacket to arrive in the mail. The 2XL suited me better and leaves more room for layering if needed. The sleeves are still a little short, but that's a pretty normal experience for me. I think it is tricky with the reversible situation, but a loop for a coat hook would be a nice add.
For reference on sizing, I'm 6'3" and weigh about 220.