Answer to some questions…
How warm… I made it to replace my montbell down inner jacket. My inner has 2.0 oz of 800 fp down. This jacket has 2.25 oz of 900 fp down so I believe this jacket is at least as warm if not warmer than my down inner. I have pushed the down inner into the teens. Its a stretch, but doable. Low temps are usually in the morning so I put the down jacket on with rain shell over it, fleece gloves and fleece balaclava or cap. I plan to use this jacket the same way.
Kinsmans size…I am almost 5'10" tall and weigh 160 lbs. I started with a kinsmans size medium. I used the athletic cut and the standard collar (opposed to wider fit and wider collar). My montbell down inner is a size medium, the fit is a bit on the small size for me. My new M50 pullover is a better size for me than the down inner.
Arm sizing…this is where Brendan's lead way extremely helpfull. We both agreed that the kinsman arm holes are on the large size. I simple took 1" off each side of the pattern all the way up the arm. Not sure if Brendan took 1" off the entire way up or not, maybe he can comment. When I was 1/2 way through I suddenly became concerned that I had taken too much off at the wrist…i.e. my hand would not fit through. But in the end the sizing was perfect. I did sew as close the the seam esge as possible near the wrist to leave as much fabric as possible. I also made the second seam (french seam) as close as possible. If I were to do this again I would only take 1/2" off each side at the wrist and might go 1.5" off each side at the pit. Then not try to sew as close to the seam near the wrist.
Attaching the sleeve…again Brendan's help was crucial, he explained this process to me. If you reduce the sleeve diameter by 1" on each side you need to reduce the arm hole by "bringing" the side of the pattern up enough to reduce the torso sleeve opening by the same amount. To check the lines I made several measurements using string to make sure the sleeve edge and the torso hole edge were the same length. I was actually surprised by how close all the pieces lined up. They were actually closer than when I did the first kinsman.
Changing the instructions to go from sythetic insulation to down just required surprising few changes. If anyone wants pointers about what to change just let me know.
Jamie