Conclusion: After 2 times will polish (in total approx .. 30 minutes of time for all headlamps) was the result of truly convincing. Bin then immediately passed the TUV and I get my stamp :-)
The results last not forever (after about 6 weeks starting the glasses again to become dull) but since I now have the spotlight on polish briefly at every 2nd car wash no more problems. Cheaper and better not go. Therefore, full 5 stars :-)