Have now replaced this with G4 Lumen Star lamps and with the help of a new LED driver, the old 20 watt halogen bulbs.
And my conclusion: I am very impressed by the brightness and the problem-free installation of the lamps. These are quite small and thus fit in almost every old halogen light-version.
The light output is definitely higher than that of the old 20-watt halogen bulb. Only the light of the new bulbs is much colder than that of the old. But that does not bother me, but I like it very well as a base light in the kitchen. The whole kitchen is now illuminated much brighter.
Then I can only hope for a long life of the lamps. Then I am completely satisfied.