@OP - from your post it sounds like you haven't auditioned the staxes. I suggest you do. I myself have been blown away with the electrostatic sound signature. You can always try the vintage models first to see if you like them.
Btw, if...
I've always liked the sound of the HD650 from a SS amp. I've heard the HD650 at its best from a beta22. Try to audition the audio gd c-2c, it's very reasonably priced.
Bought a stax headphone from David.
It was actually one of my fastest transactions here in head-fi. It was hassle free and he accomodated my request to use my favorite courier to bring the item into my country.
Thanks again. Highly...