Some people have had theirs working flawlessly since launch and some have had to return/exchange broken 360s upwards of 5 times. I have had to return 2 360s and both lasted about 8-9 months. Just be safe and order an extended warranty with MS if you haven't already.
I've had my 360 for about 8 months now and have only recently worried about the dreaded ring of death. I was wondering how many people actually get this. Was it only on the early 360's? Or on the new ones too? One last thing. Is it possible that it is inevitable and that one day I am bound to get the ring because the 360's heat is warping the internals? Thanks.

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