I've used the mitt shown, and I think it's pretty good. No scratches, and
cleans very well. But it does not last long, because the increasing amount of
dirt trapped inside the mitt gets harder to remove (even when rubbed
vigorously over a grit guard. I usually get about 4-5 good washes before
I use the mitt for wheels and tires.
I think one of the big issues is that the mitts get handled in-transit, as
well as in the stores. Often, i will physically inspect the pads, and find
tiny specs of dirt, or even grease on them. Best to treat mitts like
fruit: the best ones you buy, and the rest you leave.