Cape Town - Mercedes team principal Toto Wolff admits Lewis Hamilton is "priceless", however there are times that the driver gives his bosses "grey hair."
Hamilton is without a doubt a star behind the wheel of a Formula 1 car with the Brit leading this year's championship by 28 points ahead of Sebastian Vettel as he chases a fourth World title.
However, it is not always smooth sailing with the 32-year-old.
Hamilton has courted controversy on and off the track, and when it comes to marketing may not always be Mercedes' best brand ambassador as he often opts to drive a Ferrari road car.
Wolff, though, says he wouldn't change anything about him as he always brings it on the track.
"He is priceless," the Mercedes F1 boss told SpeedWeek.
"If he drives a Ferrari privately, he drives a Ferrari privately.
"He's a free man, you can't lock him in a cage.
"Sometimes it gives us grey hair, but on a difficult day he is fundamentally man we want to have in the car."