JustinWilsonmy hd600 bought from assesoryjack had chinese official warranty, I kept that lame paper cover that had it. Think I bought it for around 300-320
my hd650 however, have had 2 years of abuse of long session gaming, long session music, skype , whatever I throw at it, don't remember putting it to some v moda m100 abuse test, but suffice to say I don't regret tossing the paper cover away, it's past warranty anyways lawl. think i got it from amazon for like 326 or something, maybe 306