~ 50 MB + perhaps a score related low/mid-resolution images (neither of which I've read in posts et al. as said to amount to 'too much' stuff for individual projects) and
My actual intended single-project 'research' of about two GBs of PDF.
(The test text itself was imported and delimiter-split into documents, and is about equally roughly divided among two folders; two test pics & the two, large/small, PDFs were click-dragged in.
Trash has the most elsewise in it.)
The issue is that,
When I keyboard navigate (arrow up/down) to the Binder's top-level Research folder from the (currently placeholding) Draft folder, it takes several countable, tedious, seconds to simply get by Research to (not into) its two closed principal containers of test data,
the first, 'Thoughts', itself then takes 15+ sec. to get by, and
the second, 'Reference Texts & Quotes', 20+.
(In all three cases, Scrivener is 'not responding' during the wait. Once opened during a session, Scrivener does respond quicker, sometimes 'pleasantly' so

Mostly, it seems that the 'pause' is a result of Scrivening-rendering -- even when the folders are closed. In comparison, my current 'outliner', up/down is qualitatively as quick as Windows Explorer in similar operation.
And occasionally, Scrivener actually closes itself ... spontaneously ... as I click or move out of or into Research. ('Occasionally'; however, it did it again today as I moved from an empty folder in the minimalist Draft of two folders, moved to Research.)
Details will follow as requested, as they suggest themselves as relevant. I have totally uninstalled (USING CCleaner and Regedit), rebooted, reinstalled -- with Norton off -- to no advantage. As the saying goes, otherwise and elsewhere, apps (Word, the outliner, Chrome, BibleWorks, Logos ...) run stably and respond as they 'always' have for this computer -- even most together.
(I do understand that the PDFs may tax the app and may need to be handled differently, along the lines I handle them separately now, copying only specific text*. But I had been hoping for a bit more integration and a few saved steps, input and contextual review.
But that is for another time -- a data size comparable to those PDFs is not involved here.
*Aside: As does Nota Bene, it would be nice to have a 'tool' to use that strips PDFs' (and email's) hard breaks/returns from selected pasted editor window text.)
I really do want to move to Scrivener. Yet, when I encountered this same condition in late 2014, I decided then to watch/wait a bit, and not buy Scrivener. I still want Scrivener: It checks all the boxes (and more) that I was looking for to step up from my current robust outliner (which is getting long in the tooth and it's more recent version has turned away from my use of it).