works well but may not be environmentally friendly [SEP] i have had the oral b vitality toothbrush for about a year it really does a great job and my last dental visit was my best ever no cavities or gum issues my dentist was impressed i have tried both the single and dual action heads and have a preference for the latter it just feels like it cleans better however i have one major complaint after only a year the toothbrush has stopped charging this after i fully discharged and recharged it regularly like they say you should i suspect everything in the product works well except for the rechargeable battery locked inside however i must now throw away the entire thing charger plug and all because i cannot change the ni cd battery itselfbraun please make this product more environmentally friendly