Never used mine, except when I was giving a witness statement to protect a neighbour from a vexatious litigant.
I had to laugh when my neighbour asked if I used it in general. He used to work in personnel at Vickers where the gravy train of retired Colonels was well greased. One of said cadre sent a memo around on his arrival telling everyone he wished to be called Colonel. The General Manager of the site, ex national service only, issued a memo the following day instructing that he was to be referred to as Leading Bandsman W.!