Good choice for beginners (or those with a heavy hand.) Because they require more pressure to create the swells, stiffer nibs are easier to control. Thicker hairlines than others, making it a good choice for work for reproduction.
Recommended by Eleanor Winters in her Mastering Copperplate Calligraphy (B1109) for beginners and professionals because they "provide fine line quality without being too fragile." Satisfactory for Spencerian Script.