It depends a little on how you plan on wearing it. If the idea is to use it as a middle layer under a coat/jacket, then 42 should work. If the idea is to use it as top layer on top of a chunky sweater, then I would go 44.
@sebastian mcfox goes on the list of people for whom Formosa was made to fit. That jacket fit is amazing right out of the box.
The NR conversation motivated me to finally take some photos. Kind of dreary today, so that fits right in as well.
For sizing, this is the M and I am wearing a size 50 Formosa jacket underneath. I layered an Apolis chore coat underneath it this weekend as well. I'm generally a US 40 and outwear probably fits me best with something like a 19" shoulder.
Oh, and also pictured is an Inis Meain cap.
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