Why no consistent headset control?
I have a moto  X also and I recently bought the QC20.

Commands with main button did not work (neither did the micro btw) so I installed Klitch Control and still it did not work.

Then, I looked around and changed the audio settings. I turned the audio effects off, and then it started working... (why? don't know) I uninstalled Klitch Control and it's still working. I've even put the audio effects back on and the button still works..

Hope this helps.

EDIT 05/09

Hey guys, it stopped working almost directly. Today I took care of it, and I finally managed to have something working (and free): headset button controllerTrial APP.
It fixed everything : micro OK, switch OK, only thing you can't change is the long press action which is reserved on Android phones for google now..

Enjoy your QC20!