What's the story with emergency landings in water for small planes like
C172s and Warriors? What is the best technique for executing one? What
is the most common outcome? What does the outcome tend to depend on? Of
course, the availability of prompt rescue is going to be a big factor,
but I'm more asking about the landing itself.

My instructor told me to make sure the doors are ajar before you hit,
and to expect to be upside down in the water by the time the plane
stops moving. If I were flying down the Hudson river, I'd try to get as
close to the shore as possible without hitting anything, and then fly
it down to the water level, and slow it down as much as possible before
hitting the water. I'd certainly prefer nice terra firma to a water
landing in any case.

--
Guy