I confess I OWN ONE AND PLAY IT IN SESSIONS.....

I bought it in a jumble sale for about five bob (25p) in the late 60s early 70s. It is one of the grey metal bodied jobs and is still in its original case.
I can stick it in the guitar's gig bag and play the tune, if I know it, and use the guitar to play chords if I don't.

I usually play the piano accordion so it is a nice portable substitute. Much lighter than the accordion at festivals like Whitby or Sidmouth where you camp miles from the sessions.

Even John Kirkpatrick liked it when I led a tune in one of his sessions. Plastic Bah! Metal melodicas are the only traditional melodicas