It's very tight when you first get it, making you think it's too small. However, it seems to just need a bit of breaking in; wear it around, dare to allow yourself to stretch it. It works, though order the next size up if you want maximum comfort.
I ordered the Large because I'm 5'9 210, but I have a thick build, all of my weight is muscle in my thighs and butt. Don't go with your weight, go with your size.