XFI has traction control option as well. SD TT does not
The XFI traction control option wasn't on their standard units.....and is not a simple option file you load into yours. AFAIK.... you have to send in the red box to get a black box. I'm not sure if all the new XFI's (the ones that will come standard with the 2.0) will have traction control or not... or this will still be an adder at the time of purchase...