After experiencing several times emotional discussions and disagreements about what to write on מצבות (sometimes despite verbal instructions from the deceased), I mentioned to DW this morning that I hope to put my own נוסח המצבה in my will (which hopefully will not deal with any financial issues, as those will be dealt with in better ways), so there should be no possibility for disagreements.
Ed Koch famously wrote his own.
How common is the practice (amongst שומרי תומ"צ)?