The Nikon strap is 1 inch wide. It has a thin pad of rubber on the inside surface for grip.
I'm 5' 10" in height, which is the median North American male height.
With my M5, the camera will tuck in at my waist if I sling it diagonally across from one shoulder. If I just let it hang from my neck, it goes down to my umbilicus. This is at the height that I've set it at. At its greatest extent, it could go down a 2 more inches on each side.
As for weight, for an M5, the strap is wide enough. The strap material is softly flexible, and not stiff either.