My best Pmp so far.
I have tried sony's, sans'a, and cowon j3 is the best so far.
Unfortunately I lost it, and now it is discontinued so I have been trying to replace it, I bought a Sony Walkman A 865 which was sent back due to the poor battery and poor Eq, after that I bought a Cowon Z2 basically the same sound quality than J3 but an horrible android device, this also was sent back.  
 
So now I will just wait for a "successor" of the J3, since any Smartphone nowadays is able to perform better than cowon Z2, there is no point in getting a low quality android product, J3 has basically what is just needed today, a great battery life, many audio formats support, nice amoled screen; If more video support can be added and a bit bigger screen and improve the bluetooh performance in order to send and receive files, then I will get a new cowon.  Otherwise I will just use my Smartphone which plays reasonable well with Poweramp on it.
 
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