I've seen the youtube videos and read some stories also but the numbers are very few and we don't know the full story behind it if the owner got them banged up or whatever reasons that may not have been disclosed.
Here is my personal testament. I've dropped this lens from 4 ft coming out loosely from my tripod which end up breaking my D800E camera; I've tortured this lens along with my D3s in snow which also fell face first with the lens hood on due to high winds and I still use this as my go to lens when taking pictures for indoor events. So, to me, this lens is well tested more than what the average photographer does to his equipment and it still works like a champ. I don't know if anyone can make that personal claim.