If done correctly and there is not a large amount of dirt (I'm talking a THIN layer of very light dust) Waterless wash will not scratch your paint. I would suggest check the Microfibers you are using are your technique with waterless wash.
The trick is to let the waterless soak on to the paint for a minute or so in order for the dirt to basically come right off. I use 3 towels, not 2 as most say to use. One for the cleaning in one left/right or up/down motion, the other swiped the opposite way to pull off any left over residue, and the 3rd with a detail spray to clean the rest and shine it up.
I've had friends that have used it and used too much force, or tried wiping it like a detail spray and left a ton of swirl marks/very fine scratches in the paint, which is easily correctable.
However, I won't use Waterless anymore as I have my own means of completely washing the car. I only used it when I did minor mobil detailing on garage queens and didn't have full access to water. I believe in washing a car traditionally, but, again, waterless won't hurt the paint if you know how to use it and you are not trying to clean a car that hasn't been washed in 2 weeks but is driven daily.