Never been, but drove past it a lot in December (and on other previous trips). It always looks very run down and shabby compared to Wet n Wild and the Water parks.
If you have either a flex ticket (for Wet n Wild) or hopper plus (for Disney) then I really would not bother with this place. I think it keeps going by being MUCH cheaper than the other water parks, with "buy one day get 7 free" or something like that! Years ago Airtours used to give away tickets to Watermania and we still didnt go!
Having said that, I have never personally been inside it, Im basing my opinions on its appearance from the road. Maybe someone will be along who has been and can advise you more!