I live in New Hampshire, USA. We have access to a lot of rugged hiking and climbing along the Appalachian Trail and numerous similar trails. Some of these involve water crossings over rocks or wading, scrambling over scree fields or large boulders, elevation gains/descents of over 3000 feet in a couple miles, etc. I have tried BR, UpStrap, Peak Design and found when I am in a section requiring hands free for safety or stability it is best to stow the camera for both gear protection and personal safety. The BR is a complete disaster in these situations as it requires a hand for stability in even the best of circumstances, walking on level ground. The UpStrap and Peak are much more stable, but still prone to shift unexpectedly. If you are in a climb requiring use of the hands for stability put the camera away and get it out again when you need it. It can seriously slow you down by repeatedly accessing and stowing gear, but it beats wrecking several thousand dollars of gear or getting seriously injured in a fall when the hand you needed for stability is in sudden use to grab a swinging camera.
The perfect strap does not exist.
D