Ever wonder why a colony might RTN but you can save a frag?
The problems with wild vs. aquacultured are shipping stress. Also size, often these wild pieces come in very large. They have grown to a specfic spot on the reef and get very used to the amount of light, flow, nutrients they have grown up with. Also I believe not every SPS in the wild can be properly acclimated to captive aquarium life....some will just not survive.
So the advantage of aquacultured are that they have minimal shipping stress. They are small and adaptive to the captive reef environment and will grow to the environment given, not grow and then be forced into a different environment. Also captive grown aquacultured frags are proven to survive and have good color in captive reef aquariums.
The small advantage maricultured might have over wild is that the size is generally smaller and thus they are more likely to adapt well to the captive reef aquarium.