^^^ what he said.
The key to getting depth and shine to a paint job on a car is getting the panels clean and mar free (or as close as you want it) then add protection.
That entails the following
Washing done proper (at least once a week)
Claying (once or twice a year)
Polishing the panels (at least once a year but preferably twice)
Seal or wax the finish (Sealants last longer than wax and don't have to be re-appllied as often)
The choice of products you use for each of these tasks depends on you. IMHO the word "better" is a relative term (relative to the person/company making the statement)
What you should look for in a product is the ease of use depending on your skill set, and whether or not it does what it's supposed to do to your expectations/satisfaction.
Black cars look great when they are kept up. The probelm is they show every paint defect so they require more frequent atttention.
Put together a plan of attack and post, we'll be glad to help you get started.
HTH