Hey there I go to Wallington Girls and am in year 11 so sixth form is right around the corner for me too I think that the sixth form here is quite good but other people in my class have checked out Tiffin's opening day and they said that that their sixth form is much, much better. However, all the sixth forms you have stated are grammar so i guess all have to have teachers and students that exceed normal standards so each one is as good as the other. I wish you luck in finding your perfect sixth form!
Thank you , had a look at Tiffin's but it's too far XD, I have an interview and exam for one of the sixth forms I applied to tomorrow, I'm sooo nervous