do you still have the car??? If they already have it, I think you're done. If the 2011 hasn't gone into production yet, ask them to change it to a 2012. And are the other lower deals on a 2011 or 2012???
2011 X5 35d Alpine white/black leather, bamboo, Prem, Prem Sound, Cold, Tech, Sport, Adaptive drive, 20" 214's, CA, spare, active seat package, multi-contour seats, rear climate, roof rails, side-view cam, heated rear seats, auto high beams.