I tried both the HE 400's and M100's in shop and listened to my EDM playlist mostly consisting of DnB / Liquid and I much prefer the M100's
Well the HE 400's were detailed, airy, large soundstage but this made them much less engaging and distant sounding (I tried them on various amps including a tube amp)
The M100's had a textured, clear, and extended bass (A real signature sound I have never heard before), engaging, and it was difficult to find anything I did not like about the signature.
With EDM I believe instrument separation, soundstage and resolution is less important, I think that is why I choose the M100's. I don't listen to any recordings, all synths so that's why clarity, bass extension and transient response are important to me. After listening to these two headphones I can see how someone's taste in music will influence their choice.