I don't really know what their version of "referb" means, but I can tell you from working at best buy that "referb" should be a clear indication of DO NOT BUY THIS PRODUCT UNLESS YOU WANT TO HAVE A LOT OF PAIN AND HASSLE. While we would all hope that these things really undergo a "quality" inspection, in reality, they really don't. The people that are doing these inspections are paid minimum wage or maybe a little better and quite frankly care very little about whether the product will work to perfect satisfaction or not. While they will "work" for the average consumer, Head-fiers are a little more than the average consumer, so flaws that they might not detect will bug us forever.
For example, when I worked at the customer service department at best buy, one of the customers returned a dvd player saying that the component out was not working. Because dvd players are returned so frequently, we were told to immediately "inspect" it to see if anything was wrong. The box only comes with a composite out cable, and thus, since this is all the box supplies, this is the only output we would test to make sure the unit is "working". Since it worked, the "inspected" item was put back on the shelves for open box value. Since most consumers don't even know about component output, this dvd player would work fine and thus for them they'd see no difference. Any person with a home theater system who would go and buy this item however would be tearing out his hair and returning this crappy item.
While in store returns are possible with best buy, online returns are such a pain and cost money due to shipping; you might even end up spending the amount that a new pair of headphones would have cost you all together, and you'll still end up getting the referb item back. In my eyes, it's just not worth the pain to save a fraction of the price for a possibility of this much hassle.