We went to look at the two nearest schools - I liked the idea of School A, the one slightly further away, that he might not have got into anyway because on distance criterion we're right on the edge, and there seem to be more kids in ds1's year than most of the others anyway. It is also slightly awkward to get to, it's perhaps a 25 minute walk and you can only get a bus about half way, but that would matter less to him than me. 3 out of its 4 most recent inspections were OFSTED outstanding, and the head has resisted all pressure to academise.
School B has had several good OFSTEDs, and in our borough all schools are now good or outstanding. However, comparing the two open evenings School B just round the corner from our house was much better at welcoming everyone in, offering refreshments and a look at the school's chickens as an icebreaker, and being able to choose where we spent our time, where being shown round school A we didn't seem to have a say in what we got to look at.
I still wondered about A, dp favoured B, but I did give DS1 the choice, as he has to go there, and he's really sad about leaving primary and going to secondary anyway and DS1 has chosen A.
It's not clear that there are really big fundamental differences between the schools, both are co-ed comprehensives 11-16.
I did also consider looking at a third school with a sixth form but with fairly similar intake although it's much nearer to much more middle class areas of the borough, but DS1 wasn't keen as he thought he wouldn't know anyone there (it now turns out that one of his friends from school is going there and none of the boys he hung around with most are going to the same one).
I don't agree that children can't make a good choice - even at 10 I think DS1 was capable of making as justified a choice (taking into account that I don't know all the answers either) in this question. I think it's easier when the choices aren't totally fundamental, eg we're not choosing whether or not to do co-ed and there isn't a huge gap in academic outcomes between any of the schools we're close enough to for them to be a real option.