I'd call it hassle, as the option to not have to tumble all bullets, and not to be concerned, if for some reason you had to use off the shelf ammo, is vast.
Any perceived benefits didn't appeal to me, and as far as I'm aware, it's not something the military use. It's a certainty that any noticeable difference, whether lack of barrel wear, better accuracy, better velocity etc; would be taken advantage of, yet the haven't.
Each to their own, but it's like neck turning, it's not something I'm ever likely to do as it's hassle, so I settle for quality brass, and anneal every round. I'm very happy with the results.