I actually have the ES900m, which doesn't have microphone and control buttons, but the rest is the same. 
 
For $6 it's impossible to buy a pair of earphones as good as them. I really believe that the body of the earphones are metal, even if they are not, it's made of a very durable plastic. It's nothing like the entry-level Sony or Philips earphones which are made of cheap plastic.
 
Sound quality is extremely good. The lows and mids are unbelievable, while the highs are not as good. But it doesn't bother me, as overall it's still very good.
 
I have only one concern about the build quality, it's the connection point between the end of the cord and the jack. As the cable is flat, I'm afraid of breaking the cable and that only one ear will work. And in that case I'll buy another pair of these earphones.
 
I strongly recommend them.