Just purchased a slightly used HE-500 with all the original accessories for $370. It should be in my hands tomorrow. I'll be using an integrated speaker amplifier with a headphone out to power it. It should have enough power, but I'll just have to wait and see. I'm upgrading from an HD-25-ii, so this is a real quantum leap for me. I'm ecstatic!
wow...that's an incredible buy!
I have the HD-25-1 II and HE500 myself. HE500 is definitely an upgrade but the HD25 is still a great phone