I'm not completely unfamiliar with them, as I had some in the past but they were more "field" style, as I wore them over my clothes to carry an 8" .44 Magnum when I was OCing in the middle of nowhere.
Lately I've been thinking about giving one a try for EDC especially for long road trips as I just cannot STAND sitting in a car with a gun on my waist.
I see some of the popular ones do not attach to your belt which I think would be kind of necessary to keep things from flopping around. That is the type I had used in the field previously.
I know these aren't what most people use but I was looking to see if anyone else is out there shoulder carrying---what are you using, any tips, what works, what doesn't, etc.
I like the idea of a more comfortable carry with 2 mags and the ability to conceal larger guns with the only real sacrifice being having to wear Hawaiian shirts or button-ups or whatever.