My working method is pretty fixed these days. I develop and write first draft in Scrivener (on the Mac out of habit). Then I revise and finish in Word (on Windows because I find it better). Thanks to OS X’s ability to run Windows on a Mac — Boot Camp — I can do this on the same iMac desktop (or use Parallels to run them simultaneously — which I find less satisfactory since it’s a bit confusing at times).
It’s a simple and incredibly powerful workflow for me. Scrivener is unbeatable for story development. The ability to plan, structure, and label each individual scene element is something I simply can’t live without. Then, when we’re approaching delivery, Word makes sense for finishing the job. It gives me a fresh view on the manuscript, has a few editing tools (lookup and thesaurus) that beat those built into OS X, and, of course, it’s the format I will deliver the book in. It’s also the format for post-delivery revisions too; I’ve tried getting Word files back and sticking them into Scrivener for that but frankly it’s more trouble than it’s worth.
Here, in a single screenshot, is one reason why I stick with Scrivener early on: Corkboard mode.
These are individual scenes, each with a synopsis. The colours denote the labels for each story thread. As you can see there are three in this particular narrative. So I can see at a glance the balance between the story threads, change them, move them and adjust at will. None of this would be so simple in Word.