I wonder just how 'different' all these microfibres are? I'm talking about the flat weave ones of course.
I also wonder just how many 'different' manufacturers of these cloths there are?? Mmm?
I've used the Unger ones, found them great, way better than scrim for detailing and like all micro's they can be used straight out of the packet.
Boil wash?
What the hell for? We wash ours on a cool wash, they come out clean, albeit with a few stains on now and again.
Bits left behind? Fibres and so on? Not the remotest of problems in that respect, if you are getting bits of fluff or fibres left behind then god only knows what you are doing wrong because I can use them fairly damp to dry as a bone and not have a problem.
scrim has always been an effective cloth, but not in the same league as the new microfibres, they can leave no end of fluff behind, especially if used bone dry.
Currently I use the WCW ones, for no other reason than they are reasonably priced, I find them no different in use than the Unger ones.
I have no comment to make on other makes...oh, I lie, I've used the Ettorre ones and they are fine too, and I always use the flat weave variety.
if used for full on cleaning other than just detailing then I use a hand sprayer filled with pure water and something like a 1:10 dilution of isopropanol..(or is that 10:1??

).way, way better than any propitiatory spray
I started over 26 years ago using leathers on plate glass windows and could do a job as good as a squeegee...but I move with the times...always have

Ian