Pros
Being an Interdealer Broker at TP ICAP has its perks since TP ICAP is one of the largest brokerage houses of its kind. You get the benefit of scale at the company level, and more so if you are lucky to be part of a successful desk. If the desk is a successful one, then you will likely be compensated very well, relative to difficulty of the work. It is a very social job with high client interaction outside of the office (drinks and dinners).
Cons
If your particular desk and the product that you are brokering on it is unsuccessful, it will likely be very painful for you and your colleagues. The market is fragmented with established desks having large market share and it being very difficult to change that dynamic. Exit opportunities are not great considering you are not developing any meaningful skill besides client engagement.