I don't know if there is an advantage of one over the other. What little I've read about them is that it depends on the manufacturer. Seems S&W worked out the kinks & external extractors work well for them. Kimber tried them, was unsuccessful & went back to internal ones. All my 1911s, including a Kimber, have internal & all my Bersas have external & no problems with any of them, other than a couple of my 1911s needed adjustment.