This may have already been discussed, but I thought I'd share my experience doing the toggles on this coat. I chose a very pretty but also very stiff braided leather for my toggles. It looked really good with the both the wool remnant I was using for my "muslin" and with the laminate for the raincoat version.
However, when it came to doing the topstitching on the front placket, the natural thing was to just topstitch over the ends of the toggles, along with the seam allowance. Problem with that is that then they are forced to lie point "outwards", whereas when you close them they pull towards the center of the coat. I didn't notice this until I was done with the first version, and it definitely distorts the placket when they are closed. Ah well. Might not be a problem with a thicker coat material or a thinner toggle cord.
My fix for the 2nd version was very simple - just clip into the seam allowance on either side of each toggle attachment point, then flip that part of the seam allowance out towards the sides of the jacket, the opposite of the rest of the seam allowance. Then do the topstitching as normal, although it may be difficult to get around the toggle cords. I think this might be apparent to veteran sewers reading the pattern, but I missed it and definitely regret the look of my first version.
First version: http://flic.kr/p/bsWu3m
Second version: http://flic.kr/p/bFRk5H