There is a particular technique you need to master when driving downhill in an auto and that is "driving through the brakes" it is a technique you should have learned on your courses. Master it. As there is really no need for the torque lock up mod if you know how to execute that driving skill properly.
That said, if I owned an auto I would consider the mod but its not really necessary and I'd be doing other things first..
Tap this.........