https://www.auto-mot...hard-berger-f1/
with the aid of google translate:
I am often asked if Hamilton is as good as Senna. I resisted the comparison for a long time because I knew Senna well. I haven't seen a driver in a long time who has the qualities that distinguish Ayrton. With Hamilton I can now say with a clear conscience: he has it. He is the first driver I would call Senna in the same breath.
For those who may be too young to remember, Berger was Senna's team mate from 1990 to 1992 - arguably Senna's peak years - and he was also a very good friends with Senna. So if there is anyone who is entitled to make this statement, it is Berger.
The interview has other very interesting insights which I encourage you to have a look at. Berger was not only a well respected driver but also a team boss in F1 and he is currently the boss of DTM. I am not sure anyone else is in his category of experience. Perhaps only the late Lauda might compare.