Hello, "celebrities"? I don't think so. I got to know one of them (the more arrogant one - easy to discern) a bit at a long meeting some years ago. In real life he was quite similar to the way he is in the videos. They do get to test interesting cars and make videos about them - fair enough, and I am grateful for the shared experience. But that is about it. Cheers, Henrik
PS: That being said, I think that the positive verdict that the two make is genuine, not faked.
The one guy is Matthias Malmedie from the Grip Motorsportmagazine - a German show. I like the guy, because sometimes totally outrageous and going off ;-) (https://de.wikipedia.org/wiki/Matthias_Malmedie)
He's always up for a fun ride on the highway:
The other is Axel Stein - a German actor and comedian. Here also known, since he sometimes makes something with cars on TV and on Youtube. (https://de.wikipedia.org/wiki/Axel_Stein)