So, dropped off my car yesterday. Then called around four o'clock for a status update. The install was done, but the ECU update was going to take overnight. That seems weird to me that the update takes so long, but it must rewrite a whole new flash on the ECU for when the trailer wiring is plugged in; the X5 will automatically changes over to towing mod. Meaning different shift points, different braking etc. I cant believe how advanced BMW is, and the ECU comminucation with the computer is ancient speeds. We are talking 12 hours of sitting on a computer to re-flash the ECU. The only world that comes to mind is WOW!