I've heard, but not verified, that like the M5's, Nissan has a data recorder in the GTR to record all data, looking for abuse.
If you turn off the traction control, something breaks, then warranty is void.
Also, heard the trans is in the $20k range along with the breaks in the $5k range.
Never understood how/why someone would buy a supercar, then when you goto test it's super abilities, your @ss is left hanging in the wind if/when something happens.
Nissan is WINNING.....