The Nikko Falcon RC speedboat is a great water toy, specially for pools, and lakes if you're careful! My brother bought me this for christmas, and I wasted no time getting it out into the lake. Despite the ice in soem places I threw 4 AA batteries into the boat and one D battery into the controller and off I went.
The boat is quite fast for being battery powered. It turns great, and it stayed upright in the wind and waves. In the battery powered speedboat category I would rate this very highly. The only realy problem I encountered was when it went out of range and ended up going under the ice. It gets going too fast for its range in the wind and once its out of range, unless you are using it in a small area such as a pool, it's not simple to get back especially in the winter. We rescued it from under the ice and to my amazement it still worked perfectly. It's very watertight, making it quite durable. Although this past summer my little cousin threw a huge rock on it and it broke. It still went straight and turned left though.
Overall it's a great RC boat, not too expensive either. Good for younger kids in a pool i'd say. I think next time I get one it'll be gas powered though.