There are a few bugs (it reordered my chapters when I marked a chapter as edit-complete the first time. That obviously shouldn't happen).
Overall it seems like a big step up compared to Word. It can't quite keep up with the feature set of scrivener, but in exchange it has a much more approachable and clutter-free interface, much closer to the idea of distraction-free writing.
The quality of the exports is not that great. The HTML looks good for printing, but is a pain to read on screen. The epub looks good, except that it doesn't display chapter headings. The docx has 8 newlines between paragraphs when I open it in OpenOffice. I don't have a MS Word on hand right now to check whose fault that is, but it's unfortunate since I would probably go via docx to pdf.