The device is not as powerful as in the beginning. Only had it for a month. I changed the batteries, but that did not make a difference. Also, it is messy because of its design. But that is to be expected.
The water reservoir is a lot smaller than my last waterpik but I expected that as I didn't have a handheld battery operated unit before, I'm still plaese with this unit.
I chose this Waterpik model because of its size. I have very little space on my bathroom vanity. While powerful, it uses so much battery power, the power began to diminish within days, and once that happened it didn't do its job as a flosser. I had to buy the corded Waterpik WP100W to replace this travel model. I do have the space for the corded model; I'm keeping the travel model for times I may have to be away from home for an entire day or longer.