I would say that none of the above are suitable for someone who has just passed his/she test. For heavensake we are talking about a kid that is still wet behind the ears (no offense) with no experience of what can and does happen when shit goes bad. I personally think anything over 100hp is mental for the first year of driving, after this point and they have proved to be responseable then consider something with a bit more poke, but still nothing as juicy as an M car.
The more I reading these posts, the more I begin to question whether the parents in the US have more money than they have sense.
An example, my son will be driving in 2 years time and I have already picked out the car for him, whether he likes it or not.
A 1.25L Ford Fiesta.