Thanks for the feedback. Wasn't really trying to promote them per se. Just throwing them out there for consideration because they had so much good press over there. I tried them for my own car and I haven't been able to detect any marring at this point, but am definitely keeping an eye on it. Having said that, I haven't washed my car with one when it was REALLY dirty.
I'm pretty new to "serious" detailing, so I take most all product commentary with a grain of salt, but am trying a few things just to see how well some of them work. Realized when I tried them that I might have to polish some swirls and then relegate them to lesser tasks, but so far haven't had a problem.
By all means, if anybody tries one, realize it's at your own risk. I can only comment on my LIMITED experience with them.