Hi, new user here! 
I’m using Volumio (now Volumio 2) since 2014. I have three Raspberry Pi with volumio 2. RP 3 + IQaudio Dac +, RP 2 + IQaudio Dac + and RP B with USB DAC. I use Volumio with my Premium Spotify account, Web Radio, sometimes with a 32Gb Pendrive and 5.000 albums in my Synology NAS.
I’m a very happy user of Volumio