Got it from the dealership (they ordered, received and installed it within 3 days before my pick-up)...think it was around $150 + labor. Again, haven't heard the sound or felt vibrations since Saturday so keeping my fingers crossed. Outside of that "incident," the car drives great. I havent seen another M Sport in the NY area at all...Mine was the first delivered to that dealership and people were all over in the lot. You're gonna love it.
2011 550ix, Dark Graphite/Black Nappa, M Sport, PP2
2007 X5 4.8, Black/Tan, Sports Pkge
Retired 2008 535xi
Retired 2004 X5 3.0
Retired 1998 328i