I have the one you are looking at and while the boys used the dome in the first few weeks they now only drink from the bowl. Dicky, bless him, takes to putting his paw down the hole and splashing the water everywhere sometimes.

I have a filtered tap in the kitchen so I have no problems with limescale etc. but you do have to clean it regularly, not leave it in direct sunlight (this goes for all water for cats, fountains or bowls!) and change the filter every few weeks. The plastic parts come apart and can be hand cleaned or put in the dishwasher - the pump is easy to pull apart and rinse.

I am now looking at a stainless steel fountain as the dome/tank thing is not that important anymore.

Finally, the mat that appears in all the pictures of the Catit is NOT standard and costs about £12 if/when you can find it. It is nice and flexible though.