Number Four: Nettuno Superba (Stipula) The Nettuno Superba, made by the wonderful Italian company, Stipula, is another pen that ranks very high on my list of perpetual favorites. In fact, most of the time, it sits right about at the top! But aside from the wonderful celluloid, and high level of craftsmanship exhibited in this pen, the nib is a real treat. It's very soft, giving a feeling of buttery smooth ease as you write.
It's ranking below the Pelikan, OMAS and Sheaffer in this list only because those nibs have more flex to them, not because they are in any way better, strictly speaking. In terms of smoothness, the Stipula nibs cannot be beat, or at least not in any of their pens that I have tried! The new Nettuno pen, the Idra, has the same nib.
Alongside the Nettuno pens, the regular production pens of Stipula have the same wonderful nibs. Some have more give to them than others, but all are very nice.. The only one I own, however, is the Nettuno, so I have refrained from mentioning any of the other models in the list.
Number Three: Sheaffer Balance II The Sheaffer Balance II pen has not been without it's problems. That's one way to say it. Another would be that it's possibly one of the poorest engineering jobs to escape an American manufacturer since the AMC Gremlin. The plain fact is, though, the nibs are pretty good! The 18K version on the marbled balance II is a very nice, responsive nib. Quality control is very spotty, so you may want to try as many pens as you can when you are buying, but once you get a good one, you will likely be very happy with it.
It's not a large nib, about medium size, but it has enough give to it to make you feel as though you are writing with a flexible nib. You can almost overlook the lack of any real line width variation, because the nib just plain feels so good! I have used a fine nib, and found it to be smooth, but a bit too fine to really get the feeling of flexibility. I imagine a medium would be better in this regard.
The stub nib is not bad, but the tip is cut sharply enough that you tend to avoid putting any real pressure on it, for fear of having it catch on the paper. Despite this, the combination of the stub cut tip to give you a thick/thin line, and the softness of the nib make it an enjoyable pen to write with. I tend to give mixed reviews to folks wanting to know about the Balance II. The one aspect that pushes me slightly to the side of recommending them is the nib, and I think that's a pretty fair recommendation for a nib. When you think about all the problems it's making up for......