I use the following with great results (no scratching):
Top/horz surfaces:
Pure cotton Chenille pads (burn tested -- thank you).
Nice for just adding some Z7 (or other great wash products) and washing the top surfaces.
Upper side panels:
Chenille mitts (better for the side along with the lambs wool).
Real Lambs wool (not the fake stuff).
lower "dirt zones"
Cheap-o MF cloths down below that get tossed along with cotton shop wipes that get tossed.
I'm not sure what is best, but...
I really try to take the time to pre-soak any nasty spots before the wash to try and keep and "nasty" bits from getting caught in any of the applicators. Even so, I've found occasions where I've had to really keep an eye on the mitt, pad, whatever and also feel for any "bits of tar", road gunk that can get "caught in the applicator"/"pad"/whatever and despite all kinds of fancy claims, it WILL scratch the paint...
I also give a careful inspection to the mitts, pads, etc after they dry to see if they picked up any road tar or other bits that harden and can scratch the paint on the next job...
This is off-topic, but trying to keep the applicators segregated by top, upper side panels and lower panels (rocker, etc) helps to keep grit from getting at the panels where even the smallest scratch will be seen.
I also two sets of buckets for top and bottom (ok, overkill ... call me nuts)
I have a synthetic sponge and brushes for under car/wheel well work and am considering trying out the CMA sea sponge…