First of all, I like the concept of Volumio, which doesn't need an app to be installed on a device. This is the main reason why I went away from SONOS, and I also dislike the Auralic app (Lightning DS); even it's lightyears better than the SONOS or others I tried. I run Volumio on Raspberries 3b with a Hifiberry DAC Pro+. In one case, I feed it with a class-A power supply (split supplies for the DAC and the Raspi). It sound really great for the price of the device (approx. 500 € including metal housing). For another one, I have jeopardized an old FM-tuner which fits my QUAD 33 hifi-set. This one is not yet completed. I haven't explored every possibility of Volumio so far, but will do soon. As I mostly listen to complete albums, I use the queueing function when I want to listen to more than one album. I will check if I can do that track by track, which is sometimes useful as well. The only thing I could imagine might improve Volumio, would be to define a starting program, e.g. a radio station or an album from a DNLA/PnP source, or from a mounted volume. But that'd be really no game changer. Most important are sound quality and appless approach.