Gifted education start from younger age can achieve more and also improve the kids' hidden problems, like social skills, emotional issues and the other important point is parent education. Start from F3 is too late.
My son attended a Maths program at 馮漢柱 during P5 Christmas time (Nominated by the school), the teacher is good and the program also very interesting. I attended the last lesson before the closing ceremony. The teacher shared with us that they needed to write proposal to EMB, if the proposal being accpeted, he can conduct this type of training during holidays and he has a full time job in another top notch secondary school.
My feeling is gifted education more than multi-discipline training or education. Emotional and social skills education are equally important.