I know this is an old thread, but...I have a Roku (running Spotify), Sonos, and Amazon Fire TV.
I think the Fire TV has much better sound and picture quality than the Roku; additionally, I can go toslink directly out out of the Amazon Fire TV (as well as the Sonos, but I find the Fire TV to be a little warmer sounding than the Sonos and more detailed than the Roku).
HDMI + Toslink cables are Audioquest Vodka; there is a Valhalla on the Sonos and the Valhalla is just a touch more transparent than the Vodka (as far as I can tell).
I think the Fire TV has much better sound and picture quality than the Roku; additionally, I can go toslink directly out out of the Amazon Fire TV (as well as the Sonos, but I find the Fire TV to be a little warmer sounding than the Sonos and more detailed than the Roku).
HDMI + Toslink cables are Audioquest Vodka; there is a Valhalla on the Sonos and the Valhalla is just a touch more transparent than the Vodka (as far as I can tell).