As a reformed detailing fanatic anything made by Turtle Wax makes me cringe. For a black car I recommend a base polymer wax such as Meguiars NXT for solid protection, topped with a high quality carnauba wax such as P21S S100 or Meguiars Gold Class. Another thing to note is that if it is taking out swirls and marks, it has an abrasive element (I would assume it is a "cleaner wax") and it is worth taking that into consideration.

An awesome resource for learning about detailing I found was www.autopia.org