I'm absolutely gobsmacked!!
When I initially had my E1 "standard edition" I had the chance to go to a local meet and tryout other peeps setups. What I remember of the dac/amp combos I used with my HPs was the Burson Conductor and the Fostex HP-A8C. Which at the time I was thinking both had better SQ, the Burson more so.
Well today I revisited the HP-A8C, and to my amazement with just SQ alone, E1 "rolled" Muses edition, totally SlayeRd it!! by a rather large margin. Both E1 and Hp-a8c have a very similar sound sig believe it or not, which I think makes it easier to compare SQ differences when doing an A-B test. The biggest difference was overall smoothness.
The Fostex HP-A8C is a great DAC no question, and has many more features than the E1 like DSD, Remote, and SDcard slot just to name a few, and to be fair it was a demo version so I have no idea how much burn in time it has had, so you have to add that in to consideration.
Want to point out, that I'm not bias ether way as my HPs are Fostex and I absolutely love'em
So for what the E1 is, Muses Edition or not, makes it a awesome buy for it's price point, still today