It'll be down to the DAC as to how good these streamers will sound when plugged directly via analogue connections into any system. An A/B comparison will be the way to find out. They look good though, and I assume Pioneer will have a decent app to control them, as with their AV receivers.
Sorry to say it, but if you haven't tried the iOS app, it is crap. Browsing is a joke since you only get four rows at a time and you can't really scroll. It's one screen at the time (4 rows at the time).
There's also no way to fast forward in the tracks. I.E. if you have a 20:00 minute long song, you have to listan through 18:00 minutes to hear the last good 2:00 minutes.. This can't be a normal use...?
The sound howoever is good, but controlling the player is a joke.
There's also a bugg to pause a track if you use any Linux software on your NAS. What I'm saying is that you can't pause... And since you can't fast forward. Stopping is not something you would like to do...