I have listened to the X. I have yet to find a high end audio company where their flagship does not very noticeably out perform their lessor lines. Folks that have compared say the Z has greater detail, implying lower noise floor and is much more natural. From my listening, most would definitely want the more natural sound.
I find the X to be detailed and very sterile and analytical. I compared the X to a Pass INT-70 and Audio Research I/50. The X was on the one end of the spectrum as far as analytical (1) and I did not find it remotely engaging, the Pass was probably a 4 on a 10 point scale, surprisingly musical and engaging… the ARC was 10… minor venue details not as in your face (to me that is a good thing… to some that is not… it is much more like real music) and instantly musical and emotionally involving. My eyes would instantly close and I would get swept away with the music.
With the Z being more natural… I would have to recommend it. Of course, I also recommend finding a place to audition it. Take your time and listen to the music… the naturalness and musicality is not normally what will stick out first unless you are very experienced in listening.
