I haven't had mine for terribly long, but this binder is sooo comfortable. The material in the front is soft and provides a good amount of pressure to hide even a large chest. It doesn't completely hide a large chest, but it works surprisingly well.
My job requires a great amount of walking, running, bending, etc. And I have to say that even in triple digit weather running around, this binder held up and remained *so comfortable*. It is breathable and doesn't retain moisture terribly.
Tip: If your binder rolls up, buy some shirt stays!! I use these and they work so well.