We have been to all three waterparks. Aquatica and Typhoon Lagoon are tied for our favourites. We were not fans of Blizzard Beach.....the "winter" theme did not appeal to us in the slightest (but we are northerners....and seeing snow in Florida is quite honestly rather repulsive).
Roa's Rapids is freaking awesome, as you know. And the park is so beautiful and bright and colourful. For those travelling with little folks, the kids area at Aquatica beats either of the Disney waterparks by a country mile. And we much prefer the food at Aquatica to Disney (both price and quality).
Typhoon Lagoon has an incredible wave pool. Its the crown jewel of the park, and sooooo much fun. We also love the tropical vibe and the lushness of the foliage. Food is just so-so and super pricey. Parking is free, which is a plus over Aquatica (where its $12).
Blizzard Beach? Well, it was okay. But that's it. We found the lines long, and the atmopshere not our style. None of us have any burning desire to return.
You can check out my trip reports (see the links in my signature) for lots of photos and a full write up of our experiences at each waterpark. Aquatica is in the December 2012 report, while Blizzard Beach and Typhoon Lagoon are both featured in the August 2013 report.
Any other questions, feel free to ask

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