I like it. It is a body fitting fit w/side gussets at hip level that allow for stretch. This is a good thing because if there wasn't any give at the hip, it wouldn't fit me. The same stretch fabric used for the side gussets also line the arm hole edges allowing for give there. At first I didn't care for that, but now, w/the fit, it makes sense & I'm happy w/it. It gives as I move - I'd still prefer a wee bit looser fit in my sports vests. That said, when zipped up, it makes me look slimmer! What would make this vest even better is if the zipper was a 2-way zipper so when you sit, you can unzip it from the bottom for added comfort.
It's not a thick vest & as such, fits nicely under my sports jackets. Can't wear a thick blouse underneath but that's okay for me. What I wanted it for, was to throw on over my dry-fit tops & it works for this purpose. Assuming it washes well like my other Columbia garments, I'll be happy w/it.