Recently, on my recommendation, my friend invested €1400 in Sonos equipement. He intended to use his android tablet (google nexus) as his controller but also to store his music library. However because he cannot save playlists due to the "This queue contains only tracks from mobile devices. These tracks cannot be saved to Sonos playlists" issue he is now going to return the Sonos equipment as, in his eyes, it is not fit for purpose. I understand that the issue revolves around the possibility of an error being generated if the list is not available, however the same is true if a PC or Storage system is not available. Being able to let someone manage everything from a single table is a very attractive option to less technical users.