You got it! He says it in the Onslaught Expansion during a philosophical discussion with Lana prior to the Republic-side Meridian Complex battle.
"Do I hear laughter in there? In a ship that, correct me if I'm wrong, is currently being piloted by a droid, which, correct me if I'm wrong, is against the rules? Because if I'm not wrong, and I tend not to be, and a droid is piloting that ship, which is against the rules, then it seems to me that the rules must be wrong, because that droid is one of the best pilots I've ever seen."