PLS I was in your exact position last year and used to ask people sm questions, I live in west ldn so I was scared as I knew travelling seemed scary - st doms and twyford seem like normal state schools compared to the other top schools and are quite local to me but I chose to go LAE instead as it had greater A*-A and oxbridge offersss, also I don't recommend ncs lmao mainly bc of the social life, many of the students are introverted and there's only a specific demographic but I hear their rly good w STEM subjects ..
about the imposter syndrome, if you don't work well under pressure and are used to being the smartest at your school you're going to be insanely humbled (me rn), but honestly if your aspiring for top unis like oxbridge or lse, then id say its worth it as it prepares you as well as private schools do - come lae
( or brampton, my boyfriend goes here so I can give you his insights too)
the application process does not acc matter that much( it DOES for brampton and lae), many people who had conditional offers got rejected on results day but your p.s is amazing and the perfect balance between ur subjects, achievements and love for academia - but I would put slightly more emphasis on the school itself and what you would get out of it. I just want to add that they prefer predicted grades > p.s, you can have a beautiful p.s and a poor grade profile and they wouldn't even look at it
out of all the schools, lae is the best (not biased I promise) because its the best mix between academic and social life and the people here are so great - mixed demographic of people <3
also, w harris they force you to do 4 a levels across the 2 years and have such rigorous intensity that doesn't even benefit there student as many achieve D grades and U grades...also force you to come in on Saturdays for intervention - search hwsf on tt and youll see the harsh reviews xx
lastly, the harris entrance exams are online and on some weird server, chem was rly hard I would have failed if the philosophy exam didnt pull my score up, but overall its doable if you revise like min 2 weeks before ( their usually in like jan?) and they have practice papers on their website, i acc didn't go to the interview but its basc like an oxbridge interview - ask u hard q's and you need to show them how you think, also doable if you love ur subject and can demonstrate ur love and good thinking. i just came on results day after achieving mostly 9s and secured a place but the teachers were quite rude and snappy w most subjects running out ( context = I wanted to do bio chem history philosophy) but chem was full and they suggested i do spanish instead as they thought their skl was that worth it - i evacuated the skl after the condescending tones bye