Their naming/numbering scheme is somewhat eccentric when the HD580 is unlike any other 5-series set, and very much a 6-series set. I've never understood the logic of that.
It's not iPhone. There are many series and many headphones in each series. Last black friday this one was for $99.99 in US.
Yeah, HD600. Oh wait...
Got mine a few months ago and you really can't tell they aren't new. Fabulous gaming headset with an amazingly wide sound stage, perfect for any shooters.
they are 89 from time to time new on amazon. Also consider hd598 on similar price ( hd599 are just a refresh)