While many customised harmonicas have opened up coverplates this is not a universal preference. Jason Ricci was showing me his custom bodied Golden Melodys and expressing a very strong preference for the closed cover plate design. He likes the tone. He went so far as to play a string of licks on his harmonica and then switched to an open cover harmonica to show me how different the two sounded. Of course it was all amazing but if he likes the closed cover design I'm not going to argue. fjm