Pros
Good pay and benefits package, competitive salaries (particularly for those of us who aren't professionally qualified, for instance admin/customer service salaries in the private sector are nowhere close AND you would have to pay for your own travel to and from work in London). The staff passes for self and partner (nominee) are invaluable, as is the final salary pension scheme in the current climate.
Cons
You go into this company hoping to work hard and move up. They tell you when you go in you can go as far as you want, it's all down to you - I was bitterly disappointed to be honest! In reality when promotion opportunities come up you'll come up against far more experienced candidates, who will get the job cos they've had more experience (hence their examples in a competency interview will be better than yours and score higher points). Also when a lot of managers figure you're a good worker they reward your hard work with "you can't go - I need you". Which is tough if you want to go for secondments or job shadowing for your personal development. Senior managers don't care about people any more, just about the work. This has led to motivation dropping to rock bottom and lots of people are now just eyeing up the Voluntary Severance (VS) payment if it's ever offered to them and making an exit plan, having lost all hope of moving up within TfL. A lot of who you know, not what you know, and they don't always reward the most hard-working staff here. Hard to get rid of staff who underperform or don't pull their weight too. Lots of managers don't take appropriate action against such staff as they're too afraid of the unions.