We offer “full page” rendering using PhantomJS (soon to be headless Chrome) for Versionista, a competing product. It works rather well, but it introduces its own set of problems... eg you need timers to ensure all the AJAX calls have completed, and so on.
I found the 'crawl' settings a little confusing, as the first item is about loading additional URLs (which is what I thought I wanted, as JS is often loaded from separate URLs rather that being embedded in the HTML), but then there's a later option about a full browser. I chose this latter option, and left the other one unchecked. I hope that's correct.
