Pros
BC Seoul is VERY well paid in the industry. There is huge amounts of overtime going and the base salary is very nice: up to 750 pounds sterling per month, 2.3 million won local per month, 830,000 rent allowance per month, medical insurance, flights, bonus and tax-free for the first two years. If you're not saving a thousand pounds a month there is something wrong. When you work it out it is like earning 50k in the UK. Professionally, you will teach on a huge range of courses, thus giving you a beefy CV and coupled with the professional development (CELTYL / TYLEC, DELTA, PGCEi, MA) you'll come out on top. You'll also get very good support from your colleagues The centre has very good management these days who are responsive and understanding in most cases. As of now (September 2011) there is a positive atmosphere in all three centres in and around Seoul and people seem to work well together. Good holiday allowance and from 2012 these can be taken flexibly.
Cons
That said, management seem to promote those already in their 'circle', though this may be a perception amongst the bitter rather than the truth. Very, very long hours including early morning starts - 7am classes meaning you'll wake up at 5ish.