The battery stays charged for a long period of time. My waterpik is the perfect size as easy to handle. The nozzle works well; however the pressure could be higher, and the reservoir could be a little larger.
Love this portable water pik. I can use it in the shower and no mess! Plus easy for travel too. Battery lasts a week or so depending on how often I use it.
I have long been skeptical of using a water flossing device because in the past, I don’t think I was using it correctly, and I certainly did not use the type of nozzle with bristles at the end. I decided to give it another shot and boy have I been extremely pleased. My floss and then use the water Pick, and by the time I get the brushing, my teeth are so much cleaner than they used to be. It is very a satisfying experience and now I actually look forward to brushing my teeth and I never miss an opportunity to use the waterpik. I purchased the traveler version, but I also own the countertop one as well because it holds more water and has stronger pressure. There ergonomics and ease of holding are also different. But the portable version can travel with me on trips. The battery lasts about 2 weeks on the portable so it is very convenient. Both unit types are equally convenient to use for different purposes. I have purchased a total of five thus far, giving them as gifts to others. I already have plans to give two more because there’s nothing better than the gift of health.
This is my first experience with the WP-580 (I only tried one other Water Pic, and that was 40 years ago and I don't remember my experience with it). My only concern is that the water reservoir does not hold enough water (I fill it 4 times to use). Other wise, I'm happy with it.