Cantonese sound best when reciting T'ang poetry, Mandarin in Sung lyrics. Cantonese is closer to ancient Mandarin of the old. If you want to be technical, today's Beijing Mandarin is the pronunciation of the Manchus and Mongolians. They are not even native Chinese. Linguistically, Mandarin from Sian, Kaifeng would be purer.

I think it is an interesting topic. I am speaking Madrain all the time before I went to Canton for college. But when I am in Canton, people speak so hardly understand. It is no appealing to me. After I studied Cantonese several years, I found Cantonese was so amazing. That's pretty cool when you use it to read ancient poems. Haaa...

cantonese

Mandarin sounds strange in Hongkong, but the same circumstances, cantonese sounds weired and not that appealing in Beijing. So I derive the conclusion that one kind of accent suits where it really belongs, which means it feels good when you sound like the majority sound at a certain place. BTW,I like your picture. haha ~~

your question suggests that one variety is perfect and the other imperfect!. This is a very fascist reasoning. In any case, Mandarin is not any language. It is a coiné created to serve as the tool of a centralist administration. (not talking about present time). Anyway, its own name shows it: "mandarin". In my opinion, i dont know which sounds more appaling cause in China, everybody speaks a dialect or another and the perfect mandarin i never heard of. But i like south china more than northern china.