How do these two nibs compare? I know the Falcon is much finer without pressure but how about under flexion? How do they compare for smoothness, "softness", wetness, line variability, etc.?

I can not give you the answer to your questions but I can tell you that the Densho nib can easily be pulled out and switched "at home" if you end up deciding to do so. I don't know if that makes any difference to you, but I just though I would throw out that fact. I REALLY like the Densho, but I have a stiff nib on mine. JC