So far, so good
I have gone through three different cordless  water flosser this year. This one seems the most hopeful. For now, I will give it a 4 star but will update in a couple of months. The reason I am so hopeful about this one is because the entire mechanism is encased so not exposed to water that may cause internal deterioration such as rusting or electrical issues. I am hoping that this unit will last longer than the others.
Rating: 4 stars