I was parked at Sun'n'fun during the 2011 tornado, so got to see plenty of failed tie-downs.
In one case the tie-down worked, but the wing broke!
I used fly-ties and they held well within a few yards of the path of the tornado and a few wrecked aircraft nearby (my tent got flattened and all my stuff drenched, but that was OK everything considered)
I did see one of the Claw tie-downs break across the cast steel arm, but it was tying down a Grumman Mallard at the time.