I have the Califonia car duster and here is my experience. The smaller one for the inside of the car is great. Quick clean up for dust, etc. on dash and into the air vents. The larger one for the outside is great when the car is just washed/waxed and there is only "inside the garage" dust. I unfortunelty have used it on slightly heavier dust and believe it has given my black beauties ('99 ML320 and '99 CLK320) some swirl marks. The swirling is not real bad but will require using the Gold-class swirl reducer every few months when I would do the usual wax job only. I guess it is not that much more work for the 2-step process each time, and it seems that black get the swirls to some extent no matter how caareful you try to be with washing. We get lots of caked on mud around me, so the washing is essential weekly and makes it tough to avoid the swirls (and yes I use three different washing mits and change the water three times during cleaning).

Eddie.