Pros
Working at Barclays has so many opportunities. You never really need to leave. It also has fantastic pension, annual leave, healthcare and the pay is pretty good. The bonuses are great. It is a very comfortable place to work. It is quite easy to network and move your way around. Its very 'PC' and friendly. Social scene can be varied. People are generally out of the office by 5.30pm and your work life balance is mostly respected.
Cons
You have to play the game, rather than just be good at your job. There are so many people that you really have to work smart to stand out/avoid being a number. But everyone is kind and fair and so long as you work out how to play the game, the sky is the limit really. It can become quite stale with very little breadth to roles (i was there 6 years) but i enjoyed my time there and it has set my career up for the future - people really respect the name on your CV.