I actually have a tesco mitt which i used on my old BLACK MG, and it did not leave any swirls or marks at all, so it is safe to say good to use on the 350.
It is a mitt with lots of little bits coming out of it, hard to explain and i do not know the terminology, but very good as it pulls dirt and grit away from the surface, thus not scratching your car. AND goes in the wash at 30