I have used
Souveran over #7 and like the combo.
However, I hate to say it but to me Mothers Carnuba is a better product than Souveran.
Souveran often leaves oily wipe marks behind. It also sweats and leaves behind a white oilyness after sitting in the sun for a few hours.
But to answer you question, yes I have up until last week always found # 7 followed by a good Carnuba to be the best look possible on dark cars. I just said what the hell, I will try Zaino on top of the #7 to see what it looked like.
Very impressed with the look, but like you will stick with just straight Zaino on cars I don't see but twice a year or so.