Review (5/5): Love the Sonicare for Kids!
I purchased the Sonicare for Kids from my children's dentist, and love it! I have a 5 year old and 8 year old, and they share the base, and each have their own toothbrush head. The toothbrush heads are designed so that there is one size for 4-7 year olds (which my 5 year old uses), and another size for 7-10 year olds (which my daughter uses).
The toothbrush heads have held up very well, and show little to no wear in the 3-4 months they were used (the recommendation is to replace the toothbrush heads every 3 months).