I will start with the disclaimer that I am no audiophile or expert, and I have to say that I enjoyed the Essence until I upgraded to the Omen Defs. However, the Omen Defs are not that far away from the Def mk ii (especially with a few mods)and maybe even better in all categories except the bass (direct quote from Sean Casey). Both the Omen Defs and the Superfly excel with dynamics, sound staging, and are both very musical. The Superfly produces a bit more of an intimate feeling for me, though they both sound like you are at a live show....with great presence and tonality. I never got that from the Essence. The Essence excelled with vocals and jazz, but when things "got busy" so to speak, especially on the high end, my ears fatigued at even low volumes. This only happens with the Defs for me at higher volumes for longer periods of time, and with better amplification, it keeps getting louder and longer before I fatigue!
I am loving the Pass XA 30.5 at the moment, though I do have a Carissa 845 on the way. If the Pass is displaced, let me know and I will give you a great price on it.