[Sam21]

I hear both have a large soundstage. MA900 has amazing 70mm drivers whereas AD700x has 53mm drivers...
 
for music(All genres) and gaming(FPS & RPG & etc), which one would you buy and why ?

 

[kookoo]

Driver size has no bearings in the final output.
I would pick the MA900 because the Audio Technica 3D wings do not fit me well at all so comfort goes to the Sony.
I prefer the sound from the MA900 as well, it's like a HD650 minus some of the mid bass.