Pros
They allow you to be flexible with your working hours when it works for the business.
They offer a lot of socials and events if you live in London.
Cons
They say they are all about working from home and flexible hours and a good work life balance, but this is not really true.
You have to go into the office on lots of days, and if you spend time travelling you have to make that time up later, but they know when they hire you that you might have to travel for hours to get to the office. They also do not let you use the WiFi on the train, so you cannot work while you travel, and you have to make up those hours in your own time instead.
They do not give you a pay rise to keep up with the cost of living going up. They say they pay more because the office is in London, but it is not really more than what other companies pay outside London.
They will not pay back your train ticket if you go to a meeting, unless the meeting is with a client. But they still make you go into the office on lots of days where there is no client there at all.
It feels like they care more about making money than about the people who work there.
This is not what they say about themselves, so I would not recommend working here unless you live in London, and even if you do, there's probably somewhere with nicer management to work at.