I too agree with JCL.
In normal driving conditions, when DSC is on, it won't interfere unless the car senses traction loss /wheel slip. So why turn it off when it is essentially off until it is really needed?
Unless you drive the X5 very aggressively, having DSC on should not change the way the car drives.
BTW, one thing I have always wondered... If the DSC does kick in to aid with car control, does the DSC light turn on indicating that it's doing something?
The handful of times I've been in an emergency situation with the X, my eyes were fixed elsewhere...
Rui