Simply, IMHO the best fig doesn't exist.
What is the most beautiful woman (or man) in the world? The tastiest food? the...
One person, one opinion.
I long ago gave up on finding the best fig based on the opinions of others.
Of course, I appreciated a lot this kind of topic and it helps a lot, but I have concluded that the best fig I will find tasting it myself. And it will be the best fig for me, but very probably, not for my wife (it is true!).
Coming back for your question, unfortunately I have not tasted Black Madeira yet. I can't opine.
After several years tasting figs, new varieties still continue to surprise me, I continue my search.
By the way, the best fig for me so far is a well ripened (it is not easy in my climate) Coll de Dama.