I bought this item approximately one month ago and have experienced a wonderful clean feeling in my mouth. My teeth no longer have that slippery feeling after brushing - now they have a squeeky clean feeling.
I've used the cordless rechargeable Waterpik for years, but it has slowly stopped holding a charge, so this time I decided to buy one that plugged in and had a larger water reservoir. Wow! I love the huge reservoir, which not only holds more water, but is very easy to clean. But, what I really like is the power! I've always used the cordless Waterpik on high, but still had to floss. With the WP-100, I no longer need floss, and it is so powerful, I can't set the speed to much more than halfway. I thought it would be an inconvenience to have it on the counter all the time, but it's small enough to just push in the corner when I'm not using it. My only regret is that I already had a separate electric toothbrush, so I didn't buy the combination Waterpik and toothbrush unit. However, my daughter will be getting braces in a few months, and she will be getting the combo unit, for sure!
I had an implant last year and has not been without problems. There seems to be "too much gum" and I was having pain and swelling around the tooth for months. I decided to try using the Waterpik to see if it would help the swelling and irritation from food getting trapped at the implant site. It has worked wonderfully. I use it every day and there has been no more swelling. I also enjoy the clean feeling for all my teeth and gums.