I've had two FetHeads (regular + Germanian version) and then decided to also try out this one. And I was BEYOND AMAZED. Especially for ribbon microphones feeding into medium (and low) input-impedance preamps.
But even with high impedance preamps that are more than 10x the impedance of the mic (which is the minimum requirement, as a rule-of-thumb) my ribbons sound markedly better, through the DM1.
More highs, clearer mids, tighter bottom. It has seriously liberated the innate potential of my ribbon microhones!
If you look at the website of sE, you'll see some graphs showing at least part of the reason why (the impedance). But there may be more technical wizardry going on inside.
I have a hunch that sE learned quite a lot from Rupert Neve when they collaborated with him (they've said so themselves), which was subsequently funneled into their VR1 and VR2 ribbon mics (one of them active, i.e. likely with some of the same electronics as the DM1). And in turn, some of that was funneled into their X1R, which has become my favorite ribbon mic so far. Even beyond the VR1 which I also tried.
Bottom-line: discard the generic "you need a Cloudlifter" and "get a FetHead" – and instead get the DM1. The build-quality is top-notch too, btw!