I bought 2 for my granddaughters, ages 4 & 5. Easy to charge, and they plug them in to an outlet next to the Model S by themselves. Got extra batteries, but range is excellent and haven't yet needed them. We have a kid friendly beach neighborhood and they "drive" to the beach. Have kept the speed on low when I am with them (their dad lets them use the higher speed). BTW, the 4 yr old is by far the better driver. IMO, it really depends on the child if a motor toy is right for her/him.
They both love them...talk about a Tesla grin!