I'm very happy with this shirt. It's on the thinner side, but I'm ok with that. There's enough stretch to the material so that you don't feel restricted. For reference I'm 5'4 155lbs and I actually ordered both medium and large. I prefer the medium because I like the length of the sleeves and also the overall length of the shirt. I don't plan to wear it buttoned up, it would be too snug across my chest. If I decide to wear it buttoned up, I'ml have to wear the medium (yesss I kept both sizes! .う'嶁檧锔) I personally feel a little messier in the large, but that's just my preference. I'm very happy with it!