^^ Excellent post!
The EX1000 is the only IEM I've sold that I've been tempted to re-buy several times. That stopped when I finally found a truly comfortable full-sized headphone in the form of the HD800 that allowed for long listening sessions AND provided exceptional SQ. I do practically all my music listening (be it IEMs or headphones) at home.
To this day I've yet to hear a more refined and capable bass like the one found on the EX1000s. The K3003's bass comes very, very close, and often appears to match it, but on closer examination with certain tracks/albums, the EX1000's bass seems to edge it out by a small margin.
I find your concept of "hyper realism" quite interesting and I think I can see where you're coming from, although we may hear things a little differently.
The EX1000s, to these ears, were absolutely incredible with well recorded and/or mastered material, of which I have plenty. For not such good recordings/masters—mostly "loudness wars" recordings being not only loud but often seriously lacking dynamics—the W4s and my customs (ES3X) were better/more suitable, more forgiving. The EX1000s on the latter material could easily become problematic, particularly at louder volumes. I also sometimes preferred the W4/ES3X on some solo violin / strings works where I felt that note weight, in particular, (and sometimes timbre, too) sounded more convincing on the Westones, IEMs where mostly the midrange, and the lower midrange, in particular, was more satisfying / lifelike.
The K3003s bridged that gap, allowing me to enjoy both good and poorly recorded/mastered material, though specially shining with the former. The K3003s on poorly mastered material seem to reach a point where they might begin to 'hurt'/'offend' my ears but never quite get to that point, allowing me to turn up the volume if I want to (though I tend not to) — this is the exact same case with the HD800s.
I'm someone who craves a solid mid-range, and for the first time, with the K3003s, I was hearing the sort of midrange I regard as close to accurate (along with the HD800s) as I've heard — not as forward, though still very enjoyable, as the ES3X's or W4's, nor, at times, slightly thin (lower midrange, in particular) as the EX1000's.
My very first K3003 listening session went on for hours on end because my ears could simply not believe that whatever I threw at this IEM, they responded with aplomb — I very quickly realised the reference filter was the clear choice for me. I had just spent £1,000—absolutely unthinkable for me to spend that kind of money on an IEM!—and had serious reservations about having spent so much (fortunately, the place I got my set from offered a full refund [with no restocking fees] if not happy with the product (no questions asked — UK law, I guess).
We seem to view the FI-BA-SS similarly, a very dear phone to me, but ultimately the K3003s provide a cleaner, more convincing, more Hi-Fi sound to these ears. BUT, I'm still not sure I want to sell my FI-BA-SS even though I do know they'll be getting very, very little ear-time in the future.
Thanks mate. We do seem to share some opinions on the 3003, EX1000 and FIBASS, which is reassuring, as age is not forgiving with our ears :D
The difference in rendering poorly master or super loud recordings between 1000 and 3003 lies, I think, in the nature of DDs and BAs respectively. On the Sonys, because they hit harder, it can sound more disturbing, while on the AKGs, although they reveal even more flaws in those recordings, they don't shout them at you. That's why I say they sound "refined". It's very interesting.