The child of left-wing Oxbridge-educated parents (one of whom went to Holland Park...), I went to a very ordinary, run-down, unhappy 'comprehensive' during the mid-80s, when teachers' strikes were pretty ubiquitous.
It was an ex-secondary modern, with many of the same teachers still there, and the narrow worldview and poverty of aspiration was tangible. It was a long way from being truly comprehensive - many kids in the area went private, a lot of them via assisted places. I hated every second and was desperate to get out; even at the time I felt like I had to fight to get the level of education I felt I needed. I don't believe that my school's problems were a result of its ostensible 'comprehensive' status, but in large part because it *wasn't* comprehensive, since so many families had gone private.
In the end, I did go to London University, then on to graduate study at the University of Oxford, where I got to see a different world...
Although I loved the learning and the beauty of the place, I hated the comfortable assumption of superiority which is still, unfortunately, all too common in that world. I saw the way the admissions process is unhelpful to state-educated applicants, not through *any* deliberate actions on the part of the Dons - most of whom genuinely want to attract quality of mind regardless of background - but rather, I think, because of their tendency to rely on a mode of discourse with which privately-educated kids are familiar, but which has a tendency to terrify - or at least flummox - kids who are state-educated.
From my own experiences, I believe absolutely that the closer an education system gets to being truly comprehensive, the stronger it will be, and that equality of opportunity, *not* choice, is what's needed.