I think you could draw most of your conclusions from Jeff's very complete answer above:
Full Keels and backing down Fin keels are more manouverable but more difficult to track straight
Full Vs Fins beating to windward Fin keels point higher and give less leeway
Stability and righting moment Fin keels have greater righting moment for the same weight
Practical effect on speed (cruising rather than racing) Full keels are slower
Blue Water implications Such as?
There are 10 kinds of people. Those who understand binary and those who don't.