This is just a seriously well made coat that uses quality materials. I'm seriously impressed at the value for $. Wool is stiff out of the box, but it will break with use. It, however, is three Cs thiccc, made to take an absolute beating keep you *warm*, and insulated from the conditions.
Stitching is robust, and then reinforced for extra durability. Buttons are double stitched, so them falling off (as happens on a lot of peacoats, or double breasted coats/jackets in general) looks like it won't be an issue for a longgggg time. Can be dressed up or down, and will for sure look as great over a grey suit as it does over the jeans and sweater I'm wearing.
Got it on a rainy, windy, and borderline below freezing day, and immediately went for a walk to test it. Performed amazingly. Warm and toasty af inside, with zero wind penetration. Size estimator that was on the website was bang on. Do not deviate from it. Zero need to downsize, if you'd like to still be able to fit a sweater underneath and maintain range of motion. If you want a more tailored fit, buy the slim, but I'd question the ability to layer with it (i.e. only buy the slim if you live a bit more south, or don't mind freezing your dick off in -30C Canadian winters from lack of layering).
Only wish I have is for a "short" option as the 46" regular size I purchased will require some tailoring to bring up the sleeves, and the length, by about 1.5-2 inches each for a fully proper fit on my 5'9"/185 frame. I can definitely understand why people refer to this as a "heirloom" piece, though. It's easy to see that this thing is built like a frickin' dreadnought, and that it will only get better with age and wear. If you are waffling between something a little less expensive (say, the LL Bean Peacoat), then do yourself a favour: Save your pennies, and wait to buy this one.