I'd like amend my earlier comment that the Super II/RS-1 combo is "absolute perfection." After a few months of listening, I came to the conclusion that I very slightly preferred the Ear+ HD with my Grados over the Super II. The Ear+ HD has a modestly more "tubey" sound than the Super II, and I find it to be a subtle but noticeable improvement with the RS-1s. I do prefer with Super II with basically all of my other cans (when I could perceive enough of a difference to have a real preference, that is).
Bottom line: I'm keeping the Ear+ HD to use exclusively with my RS-1s. :-)