I'll get nailed for this, but I thought my SS eXSTaA sounds very good with the SR-009, and it's a bit better than with the HE-60 or 007. They also sound pretty good with my ZDT > WEE transformer. Even better is my Woo WES mk1, but my luvdunhill built KGSS comes out on top with them. So, the SR-009/KGSS could be my only electrostatic headphone rig if it came down to that.