[JML]

I'm trying to decide among these:  Questyle Audio QP1R, Acoustic Research M2, Sony NW-ZX2, and the Onkyo DP-X1. A&K doesn't interest me. Your thoughts?
 
Here are my parameters:
1.  All music is in AIFF format, ripped from CD
2.  Associated computer is a MacBook Pro, and there is no Windows machine easily available for any firmware or software updates
3.  Headphone is the Oppo PM-3 (which can be run balanced, but I would have to order a new custom cable for a balanced portable source)
4.  I have a Tidal subscription, but wireless is not necessary (nice option, but I have access to MQA via my Meridian Explorer2, whenever they actually have MQA-encoded music to stream...)
 
After reading hundreds of posts about all four DAPs, and others, I have gone around and around...
 
Thanks.

 

[Johbremat]

Disclaimer: I'm a bit of a Sony fanboy.

Love the Sony NW-ZX2. Have it attached to a PHA-3 fulltime (I don't have to, but I choose to). Besides having had a long history and nothing but positive experiences with their products, the big draw for me were the phyical transport controls. The other models you mentioned mosty have the same, but not in an orientation I like nor a physicality that allows me to operate blindly.

Unsure about the others that use Android, but I know for certain that the ZX2 allows me to disable almost everything - apps and services - I don't use.

You may not appreciate being stuck on Android 4.x and that might cause issues if you're looking to install apps (something makes me think either Tidal or Spotify might not work on it?).

Until recently I was more than a little shirted about still having to deal with the WM-Port connector, but recently had visions of trying to make an octopus cable that wouldn't be possible with micro USB or USB Type-C connector.

More knowledgeable people than I may have something to say about the Onkyo DP-X1 having some QC, build quality inconsistencies?

If any of the Android players do receive firmware updates, you should be fine over Wi-Fi.

Transferring from OS X to Android is straightforward. Grab the DMG from https://www.android.com/filetransfer/ and clicky-click.

 

[Signal2Noise]

If you want to save a bit of chump change consider the Pioneer XDP-100R which is the Onkyo's little brother. High on features and easier on wallet, imo.