I've been using Ywriter for a while now, and have been using it for everything EXCEPT my writing. I store my characters and chapter notes and scenes there, but I still have my long form novel in one giant google doc. I just like the view of the Google doc editing window; I can't get used to the editing view in ywriter.
The other complaint I have is that there's no 'worldbuilding' tools in ywriter; there's really no place to put information about world rules/laws/government/religion/etc. All I can do is make a fake chapter at the end and dump my notes in there, but it's just an info pile, nothing more.
Well, there is no perfect solution that fits everyone. My worldbuilding notes and geography stuff goes into places and items, which is working perfectly for me. But my worldbuilding is not super elaborate, so there's that to consider...