Pros
Big employer with opportunities across all functions of business. Particularly strong on engineering (from hands on the ground maintenance and operations) to strategy and policy setting. The political and regulated nature of the business makes for a complex and rewarding environment to work in, with huge investment being made and a lot of change, and the core public service ethos of passengers and the railway are all well embedded
Cons
Can be bureaucratic and hierarchical and 'rule' based which can be frustrating in driving progress and recognising individuals contributions. The move to more regional organisations within the umbrella company will I am sure bring more autonomy, flexibility and innovation. The public and political spotlight however can be demoralising as the actual performance of the railway is up there with the best in Europe, and this spotlight can also drive some 'just fix it' behaviours.