Statistically, those under 25 have more accidents than those 25 and over. But, there is the factor that those under 25 are newer drivers, which is why I think it should be based on number of years driving, not age.
It really does depend on the person, though. I've had two hit and run accidents since I've been driving. I could tell you exactly what happened, what I was doing, description of the other car, and even though I had a concussion the second time, I could still give a clear statement. My dad, as my lawyer, did the recorded interview with me for the insurance company and said I did better than most adults he sees. Then there was another time where I backed three feet out of a parking spot (with an adult passenger who was looking as I was backing out) and hit a car. I got out and realized the car was in the wrong lane. I took photos, and the insurance company, which told me that they typically find that type of situation completely my fault, found us equally at fault. I have no tickets either. The friend going to DL with me is similar: good driver, has had an accident but handled it well, no tickets. She's the same age as me.
My best friend, who is 25 and I love dearly as a friend, is a terrible driver. Multiple tickets, and not even for speeding. Stupid stuff, like driving up a one way street. Another for failing to obey MD's move over law (in Maryland, if there is an emergency vehicle with its lights on, you are required to move over at least one lane and slow down, or if you can't move, you have to move to the shoulder or as far to the side of the road as possible and stop). She recently had an accident, and when I asked her what happened, she couldn't tell me. Needless to say, she was found completely at fault. I don't let her drive me at home unless absolutely necesary, and iff I had taken her to CA with me, I would have insisted on driving, in spite of the underage fee.
Actually, the more I think about it, the more glad I am that I decided to take my long-time friend with me. She's got a lot of common sense and has done a lot of travelling, and being so far away from home in a more unfamiliar place, that's the person I want with me. I'll take my best friend, who admittedly has less common sense and travels much less, to WDW one day since WDW is as familiar to me as home is.