Does anyone have experience with the warmth difference between these two jackets? I know it's a very specific request but it's been literally a decade since I've purchased down so I have little frame of reference. My last down coat was a Michelin Man esque affair from Land's End that probably has 600 fill if I'm lucky considering it was maybe $70 on sale. Anyhow, I have really long arms and the First Ascent jackets are the only ones suitable, but I can't decide on which jacket.
Couple of random thoughts:
– I live in Texas so would likely NOT need this in actual winter
– I'll likely use it over a 250 weight merino top next to my skin, covered with my wind/water proof shell
– I don't see myself doing winter camping, so really just want it as shoulder season backup for when I'm in the mountains
– I run hot while active
– If the SHTF for real, my sleeping bag has arm holes and can be worn as a parka (Exped Dreamwalker) over it
So really what I'm asking is, if the Down Shirt a good replacement for a mid-weight soft-shell in terms of warmth, or will I really want the heavier jacket in the end?
Thanks for all the help!

