I'm 44 years old, and I have issue with the whole AGE generalization here. IF, you have the maturity, you can do anything you want. My first car (early 80's) was a 67 Mustang with unknown engine mods (the guy told my dad it was all in the mufflers...LOL). I learned to drive it by learning to drift the circle I lived in for 6 months until I turned 16. After that, I always was honest with myself about when I was over my head. It's when that is overlooked that kids get into trouble. I drove the piss out of that car, but only to a point that I knew for sure I could handle it. I constantly searched for places and situations where I knew I'd be safe trying out new maneuvers. These maneuvers were never added to real world situations, until I had mastered them.It worked for me.
Now, many of the other points that have been made in the thread are very valid. At 15, you look at that $209 payment, and know for sure you can make it. It's the insurance, the maintenance, the fuel, the mods you'll want, and others which is unknown. You also don't know where your life will take you before you pay it off. Will you go to college, get married, join the service......you don't quite know for sure yet. You damn sure don't want to ever be stuck at a job you can no longer stand, because you have to be able to pay that payment. I worked from the time I was 12, and I bought that stang with cash, my parents paid the insurance, and it was all I could do to keep the thing going. It was primer grey, very reliable, bad ass, and I could never get it to where I could keep up with my dream (still is a dream actually).