@Gregio, I can't help with Spotify, I don't use it.
I'll check the other ones as soon as possible.
@Xavv, they are close, at least for the gentle clamping force and soft pads.
They also weight the same (the XTZ 4 grams less).
I find that the ATH are a bit more comfortable in the headband. With the XTZ I feel the contact point of the head after a couple of hours or so, and I need to change their position slightly (it is anyway not a real discomfort).
It may depend from the fact that the clamping force of the ATH is a tad tighter so that they distribute theis weight better on the three contact points.
And maybe also because the ATH can swivel the pads up/down, which helps finding a better fit.
Anyway I have more hair now than when I have tested the XTZ, so this may also play a role.
I will test more in these days.
In my opinion, given the 60 days money back guarantee of XTZ, I would not hesitate one single second in buying both and comparing them.
Comparing by yourself is essential, I can only help you narrowing down the choice, but you cannot and should not avoid comparing, at least 2 models.
As said, at these levels of quality it is not anymore a matter of "which is the best" but a matter of which sounds better to you.
It may be even nuances at times, which make people prefer this or the other. Really a matter of tastes.
They are both wonderful headphones.