I have always used 100% cotton towels to detail my car, so I am new to microfiber towels. I ordered some mf towels from pakshak. I hope they are as good as everyone says they are. My question is the following. Why do they not cause swirls, if they are polyester? I have always been told to make sure the towels do not have polyester in them because the will scratch. Will the cheaper mf towels from say walmart cause swirls?