I read a review of Scrivener not too long ago. The reviewer said one of its biggest drawbacks is the difficulty importing from MS Word. So, if you work with an editor and use track changes and MS Word comments to go back and forth like I do, you'll end up doing a lot of cutting and pasting to get it back in, which also means you can forget about track changes and comments. If it wasn't for that critical limitation I might have bought it.
Instead, I write using MS Word, where I've configured the grammar checker to my taste, and the document map that works with my chapter headings. The document map (available on the View tab/ribbon) is great because it lists all of my chapters; with a single click, I can jump to any chapter I want.
Like penang, I use a spreadsheet to keep track of every named item I have in my story (stars, planets, ships, characters, military ranks, etc.). I also have a Word document for my story and chapter outlines, and another one for research information and a long list of to dos. I should probably split the last file in two.
I've gotten through almost two drafts that way with minimal overhead or fuss.
Dirk