I love this shirt! I am 59 and 150lbs and I wear a size 10 pants. I typically wear size medium in shirts but based on reviews here I bought the small and the Small size fit me perfectly!! It is such a nice soft cotton material with a great fit.
I think these shirts are great for casual wear. I purchased two because they were so cute. I wear them to run errands for the comfort. The reason I like them they feel better than a plain t shirt. I got the gray and the red. The fit for me was good. I washed them, no problem. They aren't skin tight, so the tops flows which I like.
I love it! I got a large because I like my clothes flowy and loose. I should have gone with a Medium because it does run a bit big, I am ordering another one in a different color. I still like it so I don't know if I'll return it yet. I'm 5'5 140 lbs
Edit: I returned the Large, the Medium fits perfect. Still flowy and long enough.