Well, I'm still someone's son and don't have any of my own and I'll admit I've taken out my parents' cars when they have been gone. However, I've never done anything that stupid. Perhaps some of the blame rests on the parents here?
I mean, your son is young and impressionable and at an age where image and peer acceptance is critical, and you leave the keys to a brand new, high-end Benz at the house?!? Taking your friends for a ride in a killer Benz is gotta be worth about 100 Instant Cool Points.
That's like leaving a water pistol in front of a kid and saying "Don't shoot it".
Furthermore, after seeing the kind of performance Mercedes are capable of, I've always vowed to properly teach my kids one day how to drive such cars - to show them how the car can perform at high speeds and how to control it and most importantly, why NOT to drive at such speeds. The alternative is to let them find out on their own...
JMHO,