Last I checked, ProCite cost about $500; Papyrus is probably about $100.
ProCite required the text to be formatted as ASCII text and would not use
native word processor files (it was an older version that I checked,
perhaps this has been remedied.) Papyrus used almost all of the
best-selling word processor formats directly.
I never used ProCite but I know that Papyrus actually WORKS! I used
NoteBook and it's companion program for years and Papyrus was a welcome
change.
Just my $0.02 worth.
Dale Webb
PS. You can reach the author of Papyrus on the net at
RSD at appletalk.apple.com. (I hope that's right; if not, let me know and I'll
find the right address. Tell them I sent you. I don't think they'll hold
it against you! ;-)