TÜV Technischer Überwachungsverein. The Institute for Technical Testing has locations across Germany (and in many countries), applies vigorous testing procedures to products of all kinds. A TÜV certificate is a sign of the highest quality.
Stiftung Warentest. The Foundation for Product Testing, similar to Consumer Reports in the U.S., is an independent, neutral organization which tests critically over 200 products each year. Its standards are among the highest internationally, including all requirements defined by law. The media covers many of the test results.
The quality of a product is its most important characteristic. The testing results produced by TÜV and Stiftung Warentest are considered by Germans to be 100% reliable. Each have been taken to court many times for the critical scores they have given products. Neither organization has lost a court case.