I activated also the M-Track mode (and some other functions) on my Z4M roadster 4 years before and it's really a very good improvement for the Z4M. Some friends enjoy also this mode on their Z4M.
You have a little more control on your car and this is really pleasant that the DSC is not braking your pleasure in every curve.
- Press the DSC button shortly, you get the M-track mode activated with the "DTC = Dynamic Traction Control" control light on.
- Press the DSC button 2-3 seconds and the DSC will be completely disabled, with the corresponding control light on.
- Press again the DSC button and the full DSC will be again enabled.
Nobody could see this change on the car and BMW would never check this during maintenance, because all of our Z4M are out of warranty.