I have owned a Node 2, Audiolab 6000n and a Yamaha NPS303.
Bluesound Node 2: good sound quality although sounded better via my NAD D1050 dac. Great app.
Audiolab 6000n: better sound quality than the Node 2 IMO.... app was pants and no gapless playback
Yamaha NPS303: sounds as good as the node to my ears. When playing music stored on a USB drive it is better than the Node IMO. The app is good, but not as intuitive as the Bluesound. However, I have found the MusicCast app to be less buggy than the Bluesound.
Yamaha NP-S303 / Audiolab 6000cdt
NAD D1050 dac
Creek Destiny 2
PMC DB1 Gold / KEF LS50