In reply to kevin stephens:
I have the old version and the new version and use it attached to rucksack straps. I use a Sony A7R3 with a 24-105mm lens and have been climbing with it and trust my camera with it on easier climbs. The old version had a screw to lock things in place (so they couldn't be knocked loose). The new one has a lock mode (twist the release) which is better than nothing.
p.s. The trick for larger cameras is to have the mount at or just above your collar so the camera is next to your cheek and the lens points down to your sternum. It seems to stay really stable in this position.
Post edited at 17:08