I bought my first Waterpik WP-100 back in 2010, and I replaced it after 6 years!!! It did a great work!!! Is like a having a dentist in your home, I highly recommend this product. Now I will buy the portable one!!!! :-)
on the advice of my dentist I purchased this 4 weeks ago, it is amazing how well it works to remove food debris from the mouth leaving the mouth clean.