I used one for years, but actually quit before I started using muzzleloaders.
Mine was probably a little bigger than yours, but I carried a small pipe and a day's supply of tobacco in it. Purty neat and handy. Pipe and fixings were easy to get to, even in raingear and a downpour- the big reason I wore it rather than any sense of style.
I wore it inside my shirt all the time, so I figured no problem in our brush. But somehow one day I managed to snag the cord on a pretty stout stob as I was sliding down a slick steep hill.
Came very close to strangling myself. After that I switched down to a lightweight cord just so it would break free if that ever happened again.