I bought a Fiio X3, which plays 192/24 and DSD with firmware upgrade 3.2. It has 128 gig micro card storage. It has a digital out, line out and headphone out. It is relatively compact, compared to Pono, and it cost $159.00. Adding two 64 gig cards the cost was $210.00. I order it on Monday of last week and received it on Wednesday. I have loaded it up with high rez master files and have been using it in the car, work and in bed.
The headphone out is so-so. Not bad, but nothing special. Going from the line out to my portable headphone amp is a totally different story.....it is very enjoyable!
It will play any type of file available and it a simple drag and paste. Oh, and it also functions as a asynchronous DAC, for use with computer or other USB run devices.
Again, I'm not sure what Pono offers that hasn't already been available, and in some cases, much more flexible and user friendly.
Niel's unit is about two years behind the curve. However, I do hope his down load music continues to be available, so that I can grab stuff not available otherwise.