Pros
Support - as a teacher you never have to deal with complaints or difficult customers beyond an certain point. Training - colleagues tell me it's not as good as other employers, such as IH - but it's paid. Atmosphere - depending on the centre (e.g. not Martinez Campos), colleagues are friendly and helpful. International opportunities - it's relatively easy to move around in the BC. Career development - I haven't ranked this very highly, as their insistence on the DELTA exam means that some incapable people are promoted, while other very capable people are stuck in monotonous positions. However, if you have this exam, there are decent prospects. Holidays - very long, about 6 - 9 weeks (although inflexible).
Cons
Rigid hierarchy - see above note on DELTA. There is little to no flexibility within jobs and promotions are very official while unfair. False transparency - managers usually employ who they want (and know), and make the incredibly lengthy applications fit their foregone choice. This means a lot of time wasted in hopeless applications. Antisocial timetables/bad contracts - the centres that offer decent timetables tend only to offer short contracts, and those that offer permanent contracts demand antisocial working hours (Friday, Saturday, or both, as well as evenings). Inequalities surrounding contracts are famous both within and outside the BC. Teachers are only registered as working part-time (with preparation time not included), which means they fall short of the threshold for a standard pension. Managerial attitudes - due to the rigid hierarchy, and since middle managers come exclusively from teaching backgrounds, their attitude towards teachers can be painfully patronising (eliciting the obvious etc.). Decreasing pay - pay rises always happen in retrospect, and don't meet the real rise in the cost of living, so teachers are proportionally poorer each year.