My daughter went there and I know loads of people there. I loved it and regret leaving but my daughter wanted to leave (now regrets it a bit as well I think).
It has absolutely gorgeous grounds and facilities.
It's the cheapest secondary in London by far as they are getting subsidies from Arsenal football club from my understanding (not sure if that's true).
It's an amazing school if you have a son who plays football as it's a very football-focused school with connections to Arsenal and Watford. A boy from the school we know recently signed a Premier League deal.
It has quite studious serious kids for the most part and very strict teachers (at least when we were there). That's the reason my daughter wanted to leave (also the girls uniform is ugly 😂).
There has been a lot of turnover of staff at the school and I don't know how good the teachers are now. The head is very marmite and eccentric and loads have a problem with him, but I have never had any issues with him.
They are quite strict and restrictive about what GCSEs kids are allowed to do and I have heard that they lower predicted grades on purpose to stop people leaving for 6th form. GCSE results are usually quite good.
They do great school trips, but don't offer any after school clubs (not sure if that has changed). It's definitely not a bad choice in my view.
Edited to add: I forgot my favourite part about the school - an absolutely amazing door-to-door bus service that used to even drop my daughter off at her after school activity.