Solarium : it sounds to me like a good deal also. When the seller mentions the 2 yr warranty "… Sennheiser says that all products come with a 2-year warranty. But I'm not sure how the warranty works. As an individual seller, I don't think I myself can offer a 2-year warranty for you …" this tells me that the 650s are relatively new + approx. 70hrs usage = they appear to be practically new & a pretty good deal as mentioned before. I've had mine for approx. 1.5 yr with many hours of usage (use them daily) & they're still in great shape & the sound is superb. If I was in your shoes I would buy them at that price for the reasons I've elaborated. The HD650 is the best HP I've owned/enjoyed over the years, better than some more expensive ones I've owned. Good Luck.
That's just what I might do. Gonna take a look at them tomorrow. Just wish these were new at $272 :)
Any recommendations for amps? I got a Magni just last week and absolutely love it with my HD598. I also ordered a Vali with the intent of returning one of them. Which one would fit the HD650 better? (I'm thinking Magni since it's more neutral and the Vali would add more dark/warmth to the HD650).