I am not sure I am qualified to review these because I don't use headphones a lot. I had thought about paying a few hundred for a pair but stopped myself. I have used these with a Fiio E18 (kunlan). The Fiio itself is a little disappointing because on test it worked with my Motorola E gen 2, but I upgraded to the G4 and they don't really play ball. I also tried on my brothers Sony something or other that also has OTG but the same. Not sure if this Fiio likes android 6.
Anyway, used it on my laptop and it works great. Listening to flac rips off musicbee player with the AKGs and headphone dac and the sound to me sounds clear crisp and natural. There is enough but not to much bass and the balance seems great. They are relatively comfortable. All in all I think they are a very good value sub 40 pounds set of headphones and would doubt you could get much better for that type of money.
They do leak a little more than I expected. It doesn't seem to be an issue, my wife hasn't mentioned it while watching tv. All in all recommended if you are looking for similar in the price range