I get the fact that this is a "Hi-Res" player.. So theoretically, we are all listening to Hi-Res files 24b.. But for the most part.. 90% of my collection is 16/44 FLAC or lower.. I have only recently started collecting 24 bit resolution files..
My point in stating that, the X3ii has an EQ, that can alter the sound to his/her liking.
The real reason to recommend getting the E12A is the altering of the soundstage for the better, and cleaner power to have a lower noise floor. Trust me, bass boost is nice and it's in the sub-bass region; Which is perfect for my personal tastes.. But sadly, not everyone has my tastes of bass.. Lol.. I own the E12A, I love the E12A.. I recommend it to everyone that primarily uses IEMs as I do.
By the way, ngs428, this whole reply was not an attack on you.. Please do not take it as such.. I simply wanted to add to your statement as to why to buy the E12A.