I wrote a PhD thesis of about 85,000 words in Scrivener. My subject area was psychology and history relating to the First World War. I had hundreds of footnotes and references. I couldn’t imagine trying to write something like that in anything but Scrivener. As mentioned above, I tend to keep most of research material in DEVONthink, and link to it from Scrivener. I used Bookends as my reference manager.
BTW – Scrivener isn’t German. It’s an English word!