Hopefully, I'll be mentally competent to know when it's time to stop. My dad made that decision at 90. My mom will be 90 this December and I have no worries about her abilities. However, she knows that her reflexes aren't what they used to be, so she limits her driving to low traffic times of the day.
I've always thought it was too easy to get a license in the first place and have no problems with regular skills testing - for all ages.
