Review (3/5): Not reliable long-term. Not suitable for international travel (220V)
I have been through many of these. Don't expect them to last more than a year. Unfortunately for the environment, it costs less to buy one of these every year than one more reliable model.
My second issue is that the base only works on 110V. I cannot take this brush with me when I travel, since I cannot recharge it. Adding a transformer in the bathroom is not practical. I'm sure some more expensive models work on worldwide voltage, but due to overall unreliability of all those toothbrushes, I refuse to buy one. If one carried a warranty of at least 3 years, I would.