all other discussions asside, i actualy used to own a whole set of these pens and i loved them (i think they were a previous design as they looked different)
im still sometimes at a loss of not having them anymore as they probably ended up somewhere else.
however i never used them on charts, and i would be a bit hessitant to use them there, although now thinking of it i would probably have used them on a ship where the staff required the enviromental lines to be put in with color (4nm and 12 nm both in green)
now a days i hardly do chartwork anymore (A: ecdis B teaching at a inland shipping college )but now reminded of them i will soon order a bunch of them to use in instructionals for our simulator.
also found it actualy slightly amusing that a couple of “wrong” placed words kicked of a bit of a storm…
well, that was it from this side of the pond.