For reference, I'm 5'7", 135lbs (28 inch waist), and I ordered a medium.
This really is a beautiful dress! The fabric is a bit darker pink (like between a blush and mauve) than expected from the pictures, but it's a flattering color. It also feels excellent, kinda smooth and buttery. I really like the weight of the fabric too, it looks and feels high quality and luxurious. The skirt of the dress is lovely too, it has nice movement and I like that it flares a teeny bit.
I do wish some parts of it were different though, and I'll likely take this to a tailor to make some changes. The straps, even if completely extended, are a bit short. Making putting it on and taking it off kinda difficult. It also means that the cowl back doesn't drape properly, making it a bit awkward. I also wish that the neck stayed up a bit higher, because it falls just beneath my clavicle - which is fine! But it does mean that the seams on the bust sit a bit lower than they should. It also doesn't have a zipper, but I wish it did. It would make it easier to put on and off, and would allow the waist to come in a bit to accentuate the waist.
All in all, glad I bought it! But also glad I didn't buy it full price. I'll be taking it to a tailor to make the cowl back into a normal low back, take the waist in about an inch, and add an invisible zipper.