Bought this for myself and then gave it as a gift. It's amazing what food particulars are left after brushing and this gets them out. Besides it lightens teeth too!
I have had a similar model before my current one. The hand held models should have replaceable rechargeable batteries. If that's not feasible then offer a factory service to replace the batteries.
I received my water pik as a xmas gift and I LOVE IT! My teeth feel like I just left the hygienist's chair. So clean! My gums feel better too! Love the portability of it too. Ability to take it into the shower is awesome! One of the best gifts I ever reveived.
I don't think the water pik is strong enough even with it set on HI. I had a Water Pik WP-30W. It was great. It lasted me for 14 years. Then it start leaking water from the hose. That was a real Water Pik. I use my WP-450 once a night. I have to charge the unit every six days. It does not have the power of the WP-30. I thiink the WP-450 should have a better battery which is stronger and last longer.