Mangoes are similar to apples in the sense that there are so many different varieties. A bramley cooking apple is totally different from a Braeburn or a Fuji etc etc. I have six different varieties of mango in my garden. Three are sweet mangoes and three are crunchy ones that are eaten with a sour dip.
Therefore your answer will depend entirely on which variety you have tried and what your taste is
Oh yes if they are really perfectly ripe. They have such a strong flavour one can go a long way in say a mousse or in a fruit salad bulked out with cheaper ingredients. I like them pureed over ice cream as a sauce.
In the UK the Indian stores usually have the best and sweetest ones, and most come from Pakistan. They are sweeter than the South American varieties that also get exported to the UK. Generally look for the golden ones rather than the red and green ones, but even then there are differences between the golden ones also.