The main advantage of Journler over Scrivener on this behalf is that Spotlight finds single entries, not only a document as a whole.
Which is no word against Scrivener; after all, Scrivener is not designed for the purpose Journler is designed ford.
From my experience, I would recommend against all solutions that bury their storage within a proprietary database from where you won’t get it out again without weeks of hard labour. When I switched from Windows to the Mac, I could carry with me years of research material collected from the internet thanks to the fact that it consisted simply of files in standard data formats - RTF, HTML, TXT, JPG, GIF etc. (some as Word-DOC, which is almost standard and can be read by a lot of programs) - stored within a large tree of folders in folders. (I have a folder INFOBASE, and below a folder for every subject that I’m interested in. And that’s it.)
To take this with me a simple copy was enough - several minutes. Now, on the Mac, I have Spotlight (and additional programs like SpotInside and Easyfind), which makes searching more easy than it ever was and is a solution even for those cases when I had difficulties to decide in which category an entry would fit.
Besides this, I had started to work with an askSam-database on the PC for special subjects. askSam is more or less the grandfather of all information managers (its pendant on the Mac might be DevonThink Pro); however, not uncommon for grandfathers, it’s a bit difficult to handle and definitely on the decline meanwhile. To move this database to the Mac was a chore - hours and hours of copy and paste, some WORD macro programming etc. - and a lot of things got lost in the process, for example all internal links.
So, my decision as for as the research for my books is concerned was to continue with simple folders. If you write books, continuity and a long-time perspective is a must. I don’t know what will be in ten years. Maybe Steven Jobs will be gone, Apple sold to Microsoft, and I have to return to my old DOS-PC…
Journler is not inable, it’s just a bit difficult. In Preferences:Appearance choose “Use small calendar”. Then you can simply enter a date, and you’re there.