The worst thing I can say about the HEKse at this point is that it makes me want to upgrade my other equipment. It is the first headphone I have owned that is so well-rounded and so clear that I can hear the limitations of my audio chain. Before this, I heard
@WilliamWykeham's HEKv2 with his Chord Blu and Dave and the clarity of that combination was so striking that I fantasized about taking out a reverse mortgage in order to purchase the Chord equipment (I'm half-kidding). Now I think that experience would have been even better had he owned an HEKse instead of an HEKv2. (Note: I have never owned any other upper-tier headphones [including the Susvara], so I'm not saying other headphones wouldn't be as good or better.)
The level of clarity I hear with the HEKse (and that I heard with the Chord equipment) is addictive. I want more of it, more musical layers peeled back, even faster transients, even more focus, even more definition (but not to the point of it sounding bright or sterile). Whatever extended treble and laid-back mids I heard at first have come in line with the rest of the audio spectrum. Moving to the SE from the v2 takes away some of the soundstage, as I've said before, but I don't care about that. I love the more forward, energetic, "fun" nature of the HEKse. It's so much more involving than the v2 with the music I love (Jazz, Classical, Rock, Alternative, Electronic, Ambient, Brazilian Music, World Music, 80s Synth Pop, 80s New Wave, 90s Grunge). I just want to jump back into the audiophile madness and buy a better amp, a better DAC, a better streamer -- even though I've paid off my credit cards (finally) and my mid-tier equipment is perfectly fine.
So if you'd ask me now to trade my HEKse for your HEKv2, I would grip them tightly to my chest and run far far away. I really liked the HEKv2 but it turned out they weren't quite what I wanted. The HEKse are much better than I expected them to be.