Cleaning product - Recommendation?

A good friend of mine recently purchased a 2007 black S600. The shine and look of black Mercedes is amazing, but it always need much care and maintenance. Hope a really good wax or some good cleaning products may help with it. I am sure some of few you have black Mercedes. Wondering which top of the line products are you guys using and recommend to keep your black Mercedes clean and shiny.
Thanks...

If you want something over the counter, then McGuire's is the only one I would get. All there products are excellent.

If you don't mind ordering the product, then go with poor boys products.