Looking to put our 4 year old into a once-a-week swim class very soon and deciding between Harry Wright at West Island School and the ESF swim classes at South Island school. Any experience to share with either? Our son is willing to put his head underwater and generally splash around - just needs to learn strokes and how to get going now so is past the toddler-swim stage I guess. Other option might be private swim lessons - all input most welcome - thanks!