Bests & Worsts Reviews from Amazon

First review: received it yesterday, and went as per the instructions manual. 1) Charge it for at least 4 hours; 2) Fill it with water 3) Insert tip 4) Choose "low" setting... all blue lights working properly, it's a go? 5) Oh no... when I wanted to turn it on, NOTHING HAPPENED. Talked today with an Amazon representative who was extremely helpful, they'll be sending a new unit to try it and a return label for the non-working unit. So far, extremely disappointed with with what is "supposed" to be a "top-of-the-line" very expensive product. It speaks terrible about Waterpik's quality control system. (Update Aug 10, 2018). I received the replacement 4 days ago, and the new one works. Except that the nozzle tends to turn when in use, making it more difficult to aim the water stream correctly. The machine is big and bulky, but the water tank is rather small, and even with 2 loads of water it seems to me that my gum cleaning is an unfinished business. And the water suction tube in the tank is small, so when I'm cleaning my mouth, it looses suction even if there is still water in the bottom. Not happy at all with this product, I'm going to return it and ask for a refund.