Interestingly, there seems to be a general consensus that Scrivener isn’t really suitable as a research tool. @MsLogica would rather have only 10 documents in Scrivener than 100.
I can assure you that this is a dramatic underestimation of Scrivener’s capabilities 
I created a test project with over 20,000 documents. RTF, PDF (2 to 1,000 pages, averaging maybe 10 pages), and web pages.
Scrivener works just fine. It doesn’t crash, navigating between documents is just as fast, creating new documents is no problem, searching through them isn’t either, and importing web pages works as expected.
There’s only one feature that no longer works: searching the entire project. Once you have 5,000 documents, searching becomes agonizingly slow. At least with my document structure. The exact number may vary.
Scrivener’s only problem is the search function. Unfortunately, this makes the entire app unusable for large projects—at least for me—because I want to keep all my documents in the same project.
I’ve been in touch with a user who has over 100,000 documents in a single project. Everything works normally for him too, except for the search function. His workaround is to divide his documents into a large number of folders—probably no more than 2,000 documents per folder—and he only ever searches within a specific folder at a time.
So, Scrivener is perhaps the best writing app out there. And Scrivener could serve as a “repository” for a great amount of research material in every respect, if only the search function could be improved. I don’t know if that’s feasible. Maybe in version 4. Or maybe it’s already been improved in the new writing app. That would make me very happy 