Our 3 boys went to the local village primary and then on to a highly accademic and sporting, single sex, private school.
One of them sailed through and thrived, boarded through his own choice, was in the Firsts for rugby and got good results. He is an easy-going boy and thought of as being a "thoroughly nice bloke".
One has ADHD and was a PITA for the teachers to have to teach, just low level disruption. He got brilliant GCSE results, whilst medicated and a complete zombie, but was not allowed to continue to the 6th Form and the discrimination they showed was incredible. Basically they washed their hands of him, but for the 5 years he was there it was OK..
The third son never liked the school from the word go. Not sporty like his brothers, struggled academically and used to have severe panic attacks. The school found him to be too hard work to try and teach, so they "suggested he leave" after an horrific ordeal where he smashed his own face up after being yelled at for having the wrong coloured socks for basketball in Year 9. We researched many other schools and eventually he said himself he would rather go the local comp. At this point i just wanted him to be happy, so he went.
The local comp doesn't have the trips, the flashy sports centre, the theatre etc but what it does have is teachers that really really care about my son and his fragile MH. They are caring and supportive and kind in complete contrast to the masters at the private school, who were frankly, massive bullies.
So my advice is wait and see who your child is, whether they are sensitive, loud, arty, sporty, popular or not so, etc etc. You should know this by Year 4 or thereabouts. And then listen to your child when you discuss with them where they would like to go. x