IMO if you dont disable it in the tune, get into a habit of turning it off after you start the car.
Ive found that trying to do something stupid and then TC engages, its more dangerous. one time i tried to get sideways turning from a stop, whipped the tail out before TC kicked in and the rears grabbed and almost sent me into a light pole/curb, i layed on the brakes and came to a stop before that happened.
**** traction control. if you cant control the vehicle without it, you shouldnt be driving. i dont use it at all, the GT isnt powerful enough to get my rears loose (10" bfg kdw2's) even if i try popping the clutch, they just grab and i get slingshot off the line. could just be me though, driver mod ftw!