Everyone should own one of these. Even with annual dental cleanings this should be used daily with a peroxide mix to keep your teeth clean, healthy, and white. I fill the tank with 1 part 3% hydrogen peroxide and 3 parts water.
I would normally suggest to use distilled water but the cost of replacing this unit over the cost of all the distilled water you would be purchasing would be less over time at .89 a gallon. The purpose of distilled water over tap water would be to eliminate the possibility of deposits left in the unit.
If you have braces or your kids have braces or are going to get braces you need a water flosser. This one in particular doesn't take up a whole lot of space on the counter. I replaced my large tank water flosser with this because the other tank unit was so bulky and not easy to travel with. This is very easy to clean and leaves your mouth feeling very clean.
The battery lasts a very long time in between charges which is nice and there are two methods to fill up the water tank, an easy to pop open back door and removal of the tank. I advise removing the water from the tank when storing and leaving the door open to let it air out.