A mom of one of the kids in my son's preschool works at Le Petit Dauphin and they seem very nice. We went swimming with them and her kids are definitely accomplished swimmers. They seem to instill an attitude of fearlessness in the water. And are very kind and nurturing.
That said, when my son was 18 months old he was fearless of the water and I decided he needed water safety class as much as swimming. I took him to SwimBabes which was occasionally frustrating for him, he screamed a lot, it was hard for me. They're very gentle, but very firm about their routine of lessons. And they have a lot of experience doing it, 3rd generation, masters in childhood development, etc.
He learned some basic water survival skills besides just how to blow bubbles and play in the water. He learned to turn himself onto his back and float face up in his clothes for 5 minutes. It made being around the water much more enjoyable for both of us because he learned how to get himself out of trouble while still not being afraid but is at least respectful of the water. We did lessons with them for about a year. Since then he's learned more on his own from the early exposure. And he's not a graceful swimmer, but he is confident and but also not foolish. (But that also might just be his personality.)
So, I think it depends on the personality of your child. If you have a very confident, fearless child who needs some self control, then Swimbabes is a good way to go. If you want to encourage fearlessness in the water and have a timid child then I'd say Le Petit Dauphin might be better. I know nothing about Children of the Sea program.
