I'm 5'4", weigh 150 lbs, and I went with a large! When I did my measurements, I was pretty hesitant between the medium and the large. I saw the note saying if you're right at a measurement, size up, thus I did for my shoulders! The coat very comfortable and easy to move around in(that's why I took that photo being crouched)! The material is comfortable (which I often have a sensitivity to fabrics and materials), it doesn't weigh you down, and I felt like it's a nice added layer to an outfit. The sleeves are a little longer on me (crouched photo, hand mostly covered) but I personally don't mind it, especially since when I raise my arm my hands are available (my hand taking the photos). If you do plan on using the belt to close up, I do recommend just adjusting the folded material that is created so it doesn't look bunched up on you. The lining was super neat to see when I opened up the coat and a neat surprise if you were it open. The pockets are zipper pockets and BIG, which I love and I don't feel like I'll need a purse, bag, or the rest of my outfit to have pockets to carry all of my essentials.
Overall, I absolutely love this coat from how comfortable it is, the wiggle room it has, and the stunning design and features. It's honestly one of my favourite articles of clothing and a unique add to anyone's outfits/wardrobe! I cannot recommend this enough.