In USA when working tower, approach, or center, I'm "Archer xxxxx" or "Experimental Carbon Cub yyyy" on first call then abreviated to "Cub yyy" At an uncontrolled field I'm sometimes "yellow cub". I hate it when experimentals call with "Experimental aaaa" as I have no clue what I'm looking for or what their performance may be. In USA non experimentals almost always give their type.