I drift my RC18T which comes with ball diffs. They are good for drifting because you can lock them very easily. All you have to do is tighten them down and they are locked, turining a screw can adjust the tightness. BUT... you don't need them and I find them to be weaker than a gear diff would be. To be honest I would rather have gear diffs in it but they don't make one for mine.