Two comments...
The Microfiber Chenille Wash Mitts that I show in "most" of my articles and that we sell on the AG store are what I use on my personal cars. The KEY with any wash mitt is to keep it clean and un-contaminated. That means don't drop it. Also have a system for new mitts and tatty mitts. New mitts for body panels above your knees and tatty mitts (that are clean and un-contaminated), for bumpers, lower parts of cars, etc.
The Microfiber Chenille Wash Mitts we sell on the AG store are heavy duty. By this I mean they will hold up to both washing cars and going through the washing and drying machines... over and over again. The cheapie ones that look like the ones we sell will fall apart after a few washes in the washing and drying machine. (our experience).
I used this new mitt but have not been able to get to my review yet. The sparse thread count is what makes it work not a dense thread count. It seem to be very gentle to wash with and rinse dirt out easy in a 5-gallon bucket. I would say this would be a good choice for cars that you have ALREADY DETAILED and are trying to maintain a scratch and swirl free finish on.
GYEON Smoothie Wash Mitt
The real key to avoiding accidently scratching always comes down to how you touch the paint. When washing a pristine finish don't SCRUB the paint, make one or two passes to loosen the bite dirt and road film has on the surface and then rinse.
I cover this in my how-to book, The Complete Guide to A Show Car Shine