I know this has been talked about before, but i'm bringin it up again!
Short-version: 5D III + 2xTCIII + 70-200 2.8L IS II flew off a moving safari jeep. Lens broken (with canon now), camera and TC appear to have survived! It was fastened into my sports strap properly moments before hand!
Long version: I was on safari in India. I had my 5D MK III, 2xTC III and 70-200 2.8L IS II attached to my blackrapid sport via the lens tripod foot mount. I was standing up and sitting down a lot to take pictures. One time when bringing the camera down after a shot and the jeep started to move, however, where my set-up would normally stop and rest at my hip, it continued down, all the way down to bounce of the edge of the Jeep, out of the side and onto the dirt and rock path 5-6 feet below from the now accelerating vehicle! Somehow the camera had unlatched itself from the 'connectr'. Now at this point, if i where you, i would be asking if this guy had actually fastened his camera on correctly. Well I did, and i know I did because this is the second time it has happened. The first time result in nothing other than my bemused face when my camera i thought attached to my strap was not and tumbled unharmed 30cm (1 foot) into some snow. I had blamed myself for this first accident, assuming I had not fastened it in properly. So since then i make sure to periodically check that it is fastened and the screw tightened correctly. I had checked my connection minutes before on the safari and still within that short time-frame it came loose.
Comments: This is a known problem, and known by BR since they now have a 'Lockstar' to hold the connector closed. This would have saved my gear. Do new straps come with one as standard???
Conclusion : Those with BR buy a 'lockstar'. Those who do not use BR, bare this in mind before making your purchaser decision, and get a lockstar!