Your car look beautiful and I am also considering the black sapphire metallic. It passed the "wife test" when I drove one from the dealer to my house for my wife to view.
How do you find the IAS? I know from my owning a 545i for 6 years with the IAS that the quick turning and short steering radius is fun to have to turn corners at low speeds. I suspect that the new version on the F10 with the rear steering will offer the same experience at low speed as m 545i but I was wondering whether you do notice any additional stability and "comfort for the passengers" as the BMW blurbs suggest at highway speeds.