AMD are aware of this issue and if you RMA the CPU to them, they will probably replace it without too much comment, apart from keeping your RAM to 1333MHz. They will only do this once though.
As for your friend, he might be one of the lucky ones but I have done a lot of research into this subject. I am running a Phenom ii X6 1090T and my RAM is rated at 16000MHz but I won't risk my CPU by running it at is rated spec and am running it at 1333MHz. It is better to be safe than sorry.