Is it worth going if you're in Phuket? Yes. It's got some fun areas for all ages.
Is it as good as the Waterbom in Bali? No. Whilst it's owned by/run by (?) the Centara, you'd expect maintenance to be better, especially for a place that really isn't cheap. Unless you're staying at the Centara, then it's included.
Like the Waterbom, you can't take any of your own food in. Unlike Waterbom, the food inside is pretty poor. Like Waterbom, you get a free locker and can hire towels or cabanas inside. Unlike Waterbom, the locker area has some hanging off and the shower areas have some visible mould. Also, the area is much more open so even though it is a similar size, it's hard to tell as it's less leafy.
Saying that, the water areas are clean, there are plenty of attendants and there are suitably fun areas for all ages. Like another review says here, half a day is enough, really. Which for that price might make some reconsider.
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