Originally Posted by M_I_K_E
I completely agree that any pressure while the car is dusty/dirty will cause scratches. But my responses are based on the OP's situation and question.
Yea, but if he's going to wash it the California duster isn't necessary. He should just wash it. The soap/water will lubricate the car enough and lift the dustiness from the paint enough that he can safely use a wash mitt to wash it. The duster just adds an unnecessary step IMO, although for small areas of light dust in between washes they are just fine.