Something that confuses me about a formal wear knife is this: Some of the posts recommend keeping the knife fully concealed in the pocket. This is what I often do with a suit. In that case, why does the knife need to look fancy? If deep-pocket carried and used discreetly, nobody is going to see it but you! I carry a Delica or mini Ritter Grip in my suit and they both work just fine.
It seems analogous to wearing diamond studded undershorts. Who is going to know?