Just a quick tutorial about ATRAC and about electronic traction control in general. Most of you prolly know this already but once ATRAC begins to work, it is calculating each wheel speed and modulating that wheel individually. So, try not to move that gas pedal up/down while this is happening. Otherwise, the traction control ECU will have to recalc and re-apply ABS to control wheel spin. Gravity being what she is, this short pause in re-calculating can cause your rig to move in the wrong direction!
Now, when you go with larger tires, the wheels are spinning slower which in turn makes the ATRAC feel "lazy" so bear that in mind when you go with larger tires. Of course, if you re-gear the diffs to bring the ratio (to the eyes of the ECU) back to stock, ATRAC will be more responsive.
Anyway, just a quick refresher!