Consider LS only if you intend to solidify your son's chinese. Other than that there is no upside to switch in my opinion. Local school is much more demanding in terms of homework, exam and its traditional teaching method. Kids are expected to get support from parents or tutor.
Is your kid happy in school and learning? If you know the answer to this question the decision should be easy. The fact that many people would love to go to LS has nothing to do with what's best for your child.