Hi
first i should say that im not a good reviewer.So here we go!
 
first i just bought the arrow 4g 5 hours ago.And burn for 3 hours. i should say the sound is very good
you can make it flat or colour it the way you like.
 
the gear that i use:
shure se535,the arrow,and fiio 
 
Built quality
very sturdy and strong.Small but powerfull.
the casing is matt black
with 2  
 
the bass
punchy,tight, there are 3 level of bass.Personally i choose 1,but sometimes 3,
 
the treble
not to brigt.Sound separation is good.
 
the mids
listening to queen.freddies voice sounds rich un tempered
 
 
well that is all folks
i say this is a good stepping stone from e11.
Worth the money