I have the ESW10's and have had them for a long time. I have a number of other phones as well. I find it odd that harshness is being heard with them, unless the music is harsh. I recently had them recabled with TWag v3 OM I think so much of them. Single ended or balanced (they are balanced and can be used single ended with my adapter), they sing. On well recorded live music they are true to the sound and very pure. IMO
edit: at first I was not impressed with the ESW10's and didn't even use them very much. Then I used them to burn in amps and so on. They got many hours on them and the sound changed. They opened up, became very smooth but not lifeless. They are one of my favorite phones and most likely, the last I would ever get rid of. Very hard to find now. I did just order a new set of ear pads, lamb, to make sure I have some for the future. There are many fake ESW10's out there.
Interesting, I thought that was just an issue with the ESW9.
I wasn't super impressed with the ESW11 at first listen, but when I came back to them the next day I liked them much better. I think that first day all of the expectations complicated things, as a Sony PH1 arrived at the same time. When I came back and listened less critically I found that the ESW11 hit all the right notes for me, and I am quite pleased with their sound. I still don't like supra-aurals but these are keepers.