"One possible benefit to Excalibur, though, is that the high-tech round is capable of hitting moving targets, something LRLAP couldn't do. A new variant of Excalibur, Excalibur S, has a semi-active laser seeker. Once fired, the shell can home in on a laser painting an enemy target. While that would require an airplane, drone, or human actually pointing a laser at the target, that would also mean the shell would be useful against enemy ships. Raytheon is also considering a millimetric-wave seeker, which would allow the Navy to simply fire the shell in the direction of an enemy vehicle or ship and the shell would guide itself toward the target.
"According to USNI News, it might cost $250 million to modify the three Zumwalt-class destroyers to use the Excalibur artillery round. While an expensive modification, it the ships need to use something, and the cheaper overall cost of the new rounds probably makes it worth it in the long run."
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