Depends: do you have to take them (to disable core shields)? If so, take one and neuter the nearby worlds, then throw a high tier FF and your CS next to the captive settlement and throw up enough defenses to discourage casual intrusions. You should also be prepared to handle incoming CPA threat, but if you save taking it for last (ie, after a cpa) you can then blitz the homeworlds and go for the win without it being much of a problem.