The sound quality is awesome, no complaints. My primary objectives were to keep the factory head unit so the Bluetooth and MID functions would still work. I need to keep a useable trunk so this solution worked for my needs!
2011 550xi Carbon Black/Oyster, M-Sport, Premium Package, Technology Package, Electronic Damper Control, Dynamic Drive, Comfort Access, Active Seats, Surround Cameras
2013 X5 5.0 Space Grey/Black, M-Sport, Premium Package, Technology Package, Comfort Access, Surround Cameras