The Zenith is a famous chrono. The PO is chrono-diver.... I think the Panerai only gets bought if you feel the absolute *need* to own a Panerai. On paper its not competing with the other two. So *I* would say - forget the Panerai. If you violently disagree with that, then that tells you something.

Of the Zenith vs the Omega, to me it feels like prettiness vs versatility. I vote pretty every time. Again, if you disagree, then you're disagreeing....