I used to deal with the LiquiMoly team both in Germany and in the USA on a regular basis. I would consider them to be a very high-quality manufacturer of motor lubricants. They are certified for use in modern Mercedes engines.
To that end, I askef them if they are certified for use in a modern Mercedes engine, why is it when you open the hood on a modern Mercedes car, you see a label saying something to the effect of “we recommend Mobil 1”…
…to which they replied, “we can’t afford that kind of marketing!!”