Review (5/5): Great Product
I've had mine for over 2 years and love it. But you do need to lubricate the o-ring seal when changing batteries. I use Vaseline. This does 2 things: 1) helps the seal, 2) and this is most important, it helps to fully close the cap. If you try to close it with a dry seal, it won't full close. I suspect this is why so many people end up with water inside. I had a heigher end Sonicare rechargable brush before, but the battery died within 1 year. Replaceable batteries are the way to go.