Im 55 and 210 pound she. I got a 5x. It has about a 4 inch gap in the back. I wish I would have sizes up but other then that it looks awesome. The clasps in the front are very hard to latch. But once you get them there they are sturdy. The straps are a bit far cut, unless I tighten the top pretty tight they kinda fall open around my arms.
All in all for the price its going to work great for my costume.