Ex Google Search quality Rater here, based in Germany. From 2004 to 2006 I worked on SQR and "special projects", with a much better pay (maybe because of german circumstances). I've been tracking the SQR-guide since then (public version here https://static.googleusercontent.com/media/guidelines.raterh...), so I have still some current understanding. If you have questions, I'd be happy to try to answer them since my NDA has expired ;-).