We have Zodiaq (quartz) countertops in the kitchen with the matching backsplash. I love it. It looks like granite, but doesn't have to be sealed, ever, as it is non-porous. We have astral pearl. We have a 14' black granite countertop on our bar in the next room. I must say that it is harder to keep clean than the mottled, creamy countertops. Every fingerprint shows on it and it is a constant chore to keep clean because we use the bar a lot.
It looks beautiful, it is just higher maintenance, so know that going into it. We had black bathroom fixtures in our last home (rental) and that was even more maintenance than the granite. Plus, dust shows on black more than on some other colors.