I'm very satisfied with Scrivener! I'm using both a stationary Windows computer and a Macbook for my work, and having Scrivener on both, combined with a cloud service like Google Drive (just copying your project files into Drive) makes it work seamlessly. Although, I have to say that the Windows version of Scrivener lacks some of the functionality from the Mac version. Copy-pasting text from Word can really be a hassle, becuase Windows Scrivener formats the text all wrong when copying it from somewhere else.

I find that having every piece of material related to your project gathered in one place can be very time-saving - at least it is for me. Another thing I really like about Scrivener is being able to write every scene in it's own document, and then use the corkboard view to get a nice overview of the whole project with all the different scenes presented as titled cards.