I'm really just looking for good mids, but since my refund from amazon is going to be in the form of an amazon gift card, I don't know if I could buy a pair of used headphones. Maybe just save the gift for other things. I suppose I could always get an E9 later and throw my E10 on top of it.
How low do used hd-600s usually get in terms of price. 275 is really pushing it even, I'd prefer to keep it around 260 or so.
Amping the amp is never a good idea.