At the recommendation of our family dentist, the adults in our family started using Sonicare battery powered toothbrushes several years ago. The high level of oscillations per minute have really made an improvement in our dental health, and as these toothbrushes eventually wear our, we are sure to get another Sonicare brush for each member of the family.
I like that the toothbrush bases are rechargable, using a base that plugs into a wall outlet. The toothbrush heads themselves wear out like any other toothbrush, and can be purchased separately at many stores. (I've seen them at Sams, Kroger, Target, WalMart, etc.) They have small colored bands to help everyone know who's toothbrush is who's. Over time, the batteries in the toothbrush bases do hold less of a charge with each recharging session, but that is to be expected as well.
I recommend these toothbrushes all the time to family and friends, and even my older child is excited to get one. I think they are well worth the initial investment.