While trying to be at the same time a comedy and a musical, it fails on both counts. The story makes no sense, does not become believable for a moment and keeps the viewer away, unengaged because of that. To add to the merry, it is badly written (trying to avoid to call it just awful). The film fails to be even a bit funny. No humour whatsoever that would justify calling it "irresistible musical comedy".
Songs and story are badly matched. Some of the songs are good if isolated, but the mismatch with the story does not help to enjoy them, quite the contrary, they become a source of irritation.
The story, together with the different side-plots, is just bad and full of dated clichés, of the sort of "the rich are very bad/stupid/heartless/boring and the poor are very good/sharp/sensitive/interesting".
The actors come out as shallow as the story they are working in.
However, there is some cute dancing even if the choreography in general is amateurish and would have benefited from some professionals thrown in.
A pity, because Mexico used to have in the past good musical films/comedies.