Hello Johan, for me, depending on the piece I am going to record or perform, the melodica needs to mix well with other instruments and the musical piece so tone becomes the main factor in that instance. If you prefer to play one style of music and you normally only play or practice on your own or only play the melodica for fun, then finding that one melodica that works with your personal taste is all you need. If your goal is to become a melodica virtuoso then as your ability to perform more difficult musical pieces or different styles or of music your needs will change and so will your melodica. It will need to have a more full and rich sound and it will need to perform with more precision. Change is good and it also motivates. I do stand firm on only spending money on an expensive melodica only if you believe your current melodica does not perform and sound as you need. I hope this helps you.
Monsters of Melodica