Unlike a lot of folks on Head-Fi, the quality of sound reproduction is not #1 in my book. I've always been more of a gadget-lover. It's for that reason why I enjoy the ZX2 so much. Yes, the sound quality is outstanding—it surprised me just how much better it sounded compared to an iPod or even the ZX1. But I place more value on it's secondary and ancillary features, such as full-blown Android, with it's ability to play back local videos, or YouTube or Angry Birds or Tidal, or view a quick web page or two. And obviously, the battery life is the cherry on top. In my estimation, I'd like a really expensive device to be capable of doing more than just playing back music well in order to justify its purchase price. To me, the 1A and 1Z are a bit disappointing in those regards. Although, they do interest me with respect to the new S-Master chip and extra power. But I don't know if those aspects are enough to entice me to upgrade. Right now, the only new DAP that really has my attention is the Cayin i5—primarily because it's full-blown Android with all the capabilities of the ZX2, but also with a lot more power. But it too has it's draw-backs, in that it doesn't have any balanced out, is only running Android 4.4 (which frankly, doesn't have much more longevity left compared to 4.2 in the ZX2), the battery life is a lot less than the ZX2, and I have my doubts that Cayin can craft a stable, non-buggy implementation of Android. The Onkyo DP-X1 is also interesting. But I've read more than one report complaining about the flimsy 2.5mm jack, crummy battery life and buggy Android implementation. That's one area where Sony (thanks to its history of building Android phones) really outshines most other DAP manufacturers.