I was using Dialog 3 for about 4 weeks and I like the design. Nib was pleasant to use with a bit of feedback but not scratchy at all and a bit on the wide side. It was to heavy for longer use but okay for note taking.
The reason I sold it is that you can't see how much ink is left in the converter unless you take the converter out. I know, it is a small design flaw that you can avoid if you are using cartridges but I usually carry just one pen with me and I hate running out of ink. If it was not for that minor detail I would have kept the pen because it is a lovely design.
If you are using only one pen at a time, it's better to use a piston filler. You are right about the ink-thing. And we prefer to use converters so that we can write with inks which we like. Thanks for sharing, Sonik