Besides testing, my team uses phantomjs to convert pages to PDF and also to convert javascript generated charts to images. This is sad news, I'm don't think chrome eventually will add support for.
We are using it for reports and we are tailoring our HTML specifically to the reports so we haven't had that issue. If I needed Javascript it may not be the best solution.
I like that it generates full PDFs (with real text objects) though not just a static image. I'm not sure if you can generate a PDF like that with PhantomJS. I haven't tried.
Headless Chrome might solve this issue once and for all though.
Seems to work well so far.