Melodicas have a really nasty tone due to the single reeds, the keys are always too stiff, and one of the common designs has the white keys pivoting to the right and the black ones to the left, which makes fingering horribly difficult except in C. They do work as a kind of percussion instrument, the way they're used in reggae, and David McGuinness can do amazing things with them as an accompaniment to Scottish music, but they're very much a niche instrument.

Mo, have we given you any useful ideas yet?