Regardless of the encoding of your files, I see no sonic benefit to those players. Have a look at this post to get a better understanding of this "hi-res" deal:
Also, the spoiler at the bottom of this post: http://www.head-fi.org/t/646411/lossless-vs-128kbps-mp3-vs-320kbps-mp3-blind-test
The mids of the ASG-2 are kind of dry in character, which is what makes them stand out. It's a generally warm signature, but possesses one of the clearest and most engaging midranges I've heard. It uses a 15mm full-range dynamic complemented by two balanced armatures. No crossover is used either.
Seriously the ZX1 is the epitome for me in UI and software features. The X5 is right beside it thanks to dual microsd slots, DAC function, DSD playback (I tried the new alpha firmware, and DSD works), and seriously good UI. Plus it has the power to drive cans.
Interesting those threads especially the 16 bit 24 bit one. I have a lot to read but now I don't have much time. I will see in the future. I have a feeling like I should downsample everything I have to 16 bit cd quality level (sorry still I don't feel like going to 128 kbps mp3 but 320 kbps can be okay-ish).
In that case I will have more capacity and be able to use more daps like Studio V 3rd anniv (I didn't buy it before because the lack of 24 bit playback otherwise great battery life, form factor).