NC for this so that I can be blunt. I'm not a governor nor do I work for, or am associated with AB, but my son goes there currently.
AB is a bit of a marmite school. What I really value about it is the general freedom it gives its students. No uniform. No sitting in isolation due to the "wrong" haircut or shoes. Teachers seek to mediate rather than punish.
This can come with obvious drawbacks like disruption to class. The impression I get from my son is that there isn't a lot of crackdown on the disrupting kids. However, as he's moved along into the upper years, he doesn't see a lot of the badly-behaved kids because they've filtered down into the different sets, so his classes tend to be more peaceful and focused. Prospective parents might want to look into how the bottom sets are, but I can report that the top sets tend to be well-taught with not a lot of disruption. There've been a few cases where supply teachers taught for longer than I would have liked, to cover gaps, but from what I hear, that's happening in many schools.
My son has additional needs and had a horrendous time with bullies in his last year of primary (Y6) so I was very ready to act re: bullying. There were a few occasions where I felt he was picked on, and a few incidents he reported someone shoved him or the like. Every time I had to contact the school I felt listened to, although there was one case where I felt the aggressor ought to have been dealt with more robustly. Conversely, my son was hit while in the lunch line by a boy a few years above and that was dealt with quickly and with a decent amount of transparency. He's not had any incidents over the past 18 months or so.
HoY was always very responsive and ready to act when I contacted them. I think the safeguarding and some of the pastoral care is actually pretty good at the school and they are proactive when reaching out about my son's SEN. They ran a DofE expedition earlier this year which got a 100% pass rate and I'm generally happy with the extracurricular clubs provided. If you have a musically-inclined kid or someone into dance, this is a good school to look at. Acting seems to have decent provision too, along with art.
Some parents will look at the school and see rough edges and some parents kinda prefer that less-polished vibe, so it comes down to your own preferences. I like the fact that they don't hide their SEN provision or sweep those kids under the carpet. I like that my son doesn't have to raise his hand and ask permission to take off a stuffy blazer.
Could things be better? Yes. But from what I see and hear from other state schools, education all round needs major funding and TLC, and the fact that AB isn't an academy is important to me, as is the fact that they don't hand out detentions for using the wrong pen or wearing odd socks. On the flip side of that, if your kid isn't a self-starter or requires lots of external discipline in order to succeed, you might want a school that cracks down more sharply.
At the end of everything, it's horses for courses. Go along to the open evening, check things out in person, and have a chat with the student ambassadors. Look at everything as logically as possible, make a list of pros and cons, and then tap into your gut feeling. Do they reconcile? If not, can they?