I sincerely respect the effort Crinacle has devoted to producing his measurements and rankings and the portable rig he devised to measure these IEMs is pure genius, so I hate to be critical. But I'm going to be anyway...
In my experience, to really know how two very good headphones perform relative to one another, I have to spend days going back and forth. I don't know how any human being could, in their lifetime, possibly do that A/B with every possible combination of so many IEMs, even if you owned them all. joker made a good effort at ranking IEMs a while back, but he had simultaneous access to them all. I doubt Crinacle does. So I take those rankings with a very large pinch of salt. For example, he started the KSE1500 off in the B rankings and it only moved up after I suggested it was in the wrong place. (Personally though, I'm fine with his current relative ranking of Xelento and Vega!) The other problem is with his measurements. Look at his SE846 measurement. The SE846 is an IEM I know really well (and have measured a zillion times, with a zillion different cables, filters, eartips, etc.) and Crinacle's measurement looks nothing like any SE846 I've ever measured. And the differences have nothing to do with mic/soundcard/DF calibration curves - no way does its resonance peak go that far past 10 kHz under any circumstances. The other problem with this measurement database is that there's never a mention of the eartips used. That's a serious omission; eartips make a vast difference to the FR. In addition - the SE846 has many different filter options (including three stock options) and Crinacle doesn't even mention which was used. Without this information, the whole database is kind of useless, IMHO, even for internal comparisons.