I would clay the car first, then use 3M Finesse-it, then
3M IHG, then Klasse products (both) or Zaino, or Finish First(less steps, about the same shine/protection) and then
top it off with Blitz Wax, as the polymer sealants tend to make Blk look too "glossy". The carnuba will impart a nice,
deeper, wetter looking shine and will take some of the "gloss" or "gleem" off of the polymer sealants. Zaino is good stuff, but you'll be applying it forever (various steps) so Klasse would edge Zaino out slightly. Plus Zaino
is a wallet-drainer, but if you have the cash and time....
Finish First is a great, one step product and it's very easy
on the wallet. The protection is about the same as the above
products and goes on and off easily, in one step. My Black
Bimmer was actually too glossy for me (a credit to the product, as that same gloss looks good on lighter colored vehicles) so I toned it down with a topper of Blitz wax, which really gave me the protection of a polymer and the
shine of a carnuba, the best of both worlds. My buddy uses Zaino on his ride, but when we put the cars together, we can't tell which looks better, a testament to FF because it
achieves the same shine, but in one step. Cost only
17.00-20.00 bucks. It's funny, but in a "gloss meter test"
or something like that, when they tested the gloss using some machine, all of the above did well, but I think some cheap crap beat everything else out, forgot what it was though. Good luck, sorry so long.