I am questioning that anyone has heard it on the W/P8.
The WP8 uses technologies from the MAXX - my understanding is that Wilson has improved on the problem of "grain" or "etched" sound from Titanium drivers (to me the need for "improvement" is admission that Focal had resonance problems with these drivers).
I don't have enough experience with WP8's to know which music or tracks may show it up best. FWIW - silk domes have issues too...just different issues...they tend to break up and roll-off early (albeit in a fairly benign manner). Personally I don't mind this lack of linearity and I favor the smoothness that they give to sound. So you pick your poison - nothing is perfect - silk domes with lower distortion but poor bandwidth or metal with amazing bandwidth but poor internal damping...neither is better than the other - but assuredly "rigid" metal rings whilst soft domes break up!!