For me, it’s an electric toothbrush. It doesn’t matter if you go with Sonicare or Oral-B, once you start using an electric toothbrush, regular toothbrushes don’t ever feel like they clean your teeth properly. The smooth plaque-free top layer of your teeth that you can feel after using an electric toothbrush can’t be replicated with a regular toothbrush.
It is a regular alkaline battery, so no I don’t send the old one back. It is not required you can just get the brush head if you like and use a rechargeable battery that you supply if you want.