Been using one for a long time and it's great. I have no worries about scratching the finish. As long as the car is just dusty it works great but if there is dirt on the car you should wash it. I use Zaino Z-6 after I use the duster. I don't think it's a good idea to use detail spays on a dusty car even with a microfiber towel because that will more than likely do more damage to the finish than the duster will. The duster picks up the dust rather than move it around
