Flourishing in a Rigorous Academic Environment | Profiles of Success at London Schools

Who thrives in a highly academic London school like St Pauls', Highgate or South Hampstead High School?
And how do I know if my child is a potential scholar? What differentiators do highly selective London schools identify in successful applicants? How much does tutoring or attending a ‘feeder’ prep school improve admission chances?
Anna Paul - Head, South Hampstead High School, GDST
Adam Pettitt - Head, Highgate School
Dr Andy Mayfield - Director of Admissions, St Pauls School