I'm not a "huge" guy. I don't eat "lots of protein", but this jacket's chest measurement is built for someone with a fixie and a large mustache; someone who smokes instead of eating a nice burger. I am 6 foot, 175 pounds (and not seen as intimidating by anyone when it comes to my build) and this jacket in a medium fits great everywhere but the chest. I bought both the medium and the large and will be keeping the large (which is a bit baggy, but it leaves space for layering. The center back length is quite low (it goes below my butt), but that is a good thing coupled with the drawstring to keep all sorts of updrafts out. It is twice as heavy as some competitors (see montbel tackeyon), but that is literally a 2 oz difference which is negligible (and that's coming from a ultralight freak). the extra 2 ounces get you a full zip, pocket that turns into a self stuff sack, and a material that feels twice as tough as the next. The fabric feels like an ultra light, translucent cloth, not a trash bag.
I think that if you took a huge whipper into the wall with this, you might have a decent hole, the same goes for if you were really grinding on this puppy up a chimney, but I think that the weight trade off is perfect when you use this as an emergency layer. If you are looking for something to wear in a serious storm, keep looking, but this is a nice to have when the wind kicks up with a light rain.