Since I've not actually owned one, I can only surmise how they are to opperate from the many posts and threads about burning problems, draft problems and cracked cast iron..
Like on this thread: Advice on Franco Belge 10.1475
But I have seen the Harman SF150 and a Mark II in action,and have poked, prodded, and toasted my hands in front of them.... They are not finicky and are tanks.. I think you would have to forget to close the ashpan door with a full load of coal for 8 hours to hurt one.
If you can find any stove that is not broken, warped, or cracked, and is at a very reasonable price, learning to operate it is good experience..