For a legend that is Rafi, his son is so humble.Hia narration is so matter of fact, his qualities shine because of that.Gods must be having a grand time with him.
Rafi was great for Bollywood songs, but I personally like Nusrat Fateh Ali Khan more for his improvisations & classical beats, particularly qawaalis. I would say no one has replaced Nusrat & most likely there will not be anyone in future like him.
Mohammad Rafi was trained kabali singer, and had deep voice that suited the purpose. But he was technically poor and for this reason Lata, being technically adep, was not too fond of singing duets with him. After he went on Hajj he did not want to sing romantic songs, which gave Kshore Kumar his opportunity. Even today and now there are many kabbali singers who can singer just as well if not better than Rafi. Indians have unique unhealthy romantic habit of magnifying achievements of the past and down playing present youngsters.