I'm 5 foot 7, 135 pounds, so I originally bought the small since I usually wear a size 6. The small was waaaay too small. Mainly too short in the torso. So I purchased the medium. It's now long enough in the torso but a bit baggy everywhere else. There's a surprising amount of room in the shoulders. Not as nicely fitted as it appears in the picture.

That being said, the fabric is decent quality, the Star Trek logo pin is a nice heavy plastic, and the pips are metal. I'm definitely going to be wearing it for Halloween and I'm looking forward to it. So I'd recommend it, but be prepared for the fit to be a bit imperfect.