I have a Sonos, not entirely blissed about the quality. But I don't have an expensive DAC, I use a good Scott Nixon Tube DAC. Not as resolving as I would like. But clearly warmer and more musical then the Sonos DAC. What did you decide. I have just downloaded MARS to use to ripped cd's in FLAC. Better sizzle with the highs in FLAC compared to Apple Lossless maybe its the 24 Bit FLAC difference? Have you read the Transporter review in Sterephile magazine? http://www.stereophile.com/mediaservers/207slim/index2.html