Hey seadams,
I think you're deceiving yourself by thinking that 250 hours is a lot of use. It's not. In fact, I'd imagine the seller (and many potential buyers) would consider them as having only 250 hours on them. It's one album a day for eight months. There are even people that believe certain headphones haven't reached their full potential until around that many hours of burn-in. Most drivers are meant to last for decades of use, as pointed out above.
If you're worried about it, you should check the official thread. I'd probably be more concerned about pad wear (also mentioned above), but honestly, this is such a modest amount of use that I don't think it'd matter much unless you see a lot of people complaining about that particular problem... Or, I guess, if the person was particularly hard on their headphones, but it doesn't sound like it from their description.
All that aside, I'm a little confused... in your first post you seem to think they're a bargain, but in your last post you say they're not much less than a new pair? If that's true, I personally would rather shell out a few extra dollars for peace of mind... but if it's a not-negligible difference, I think used is probably fine.
As mentioned already, just make sure the seller has decent seller feedback. If so, they're not going to want to wreck their reputation by selling a bad item.
