I have many Kz iems and D Fi .D fi is one of the best but latest the smoothness of the mids of of Libras balance version is starting to win.The only drawback for me is the too much bass it masks a tiny bit the things that's a why I mod it and now it's even better.I think KZ has to put more iems with the same relaxed 3000 hz pina gain or make even higher 3.3-3.5 khz Pina mids- tuning .Its nice for many hours of use because hi hats, trumpets, female voices don t become tiresome..I also propose to make a new refined HM 20 with the same subdued 1-2 khz mids because it's VERY nice ! IF I could tune an iem I would make an HM 20 with the technicalities and the bass with the switches of the Hydro..(Just my opinion) ❤