That kills the X7 for me. I mean, for $280, I would've went for it but 10ohms right now is not something want. The X2 is gonna be my main headphone, and at 30-ish ohms, sensitive at that, it doesn't make sense to get the X7.
What specifically irritates me is how these amps are made to use headsets which are almost always low ohm and sensitive.
Can't have everything, even if they got close.
I prefer the X1 over the 598 every single time. They sound quite different so...