Pros
Good learning experience (BUT you 90% of everything you need to learn in 6 months and then start repeating yourself) Some of the old bankers are incredible and the last remnants of when IBD attracted some of the most interesting (and dare I say cleverest) people in the world - very unlikely if you join now you'll have any interaction with them
Cons
Huge nepotism - "what school did you go to haw haw" Layers of mediocre senior and mid-management Huge amounts of unnecessary work London in perpetual decline - bailed out by NYC and Paris again and again - not good for morale The CEO / partner level employees in London generally have as much charisma as a damp rag. Super firings every few months - not good for morale Losing deals in the UK again and again Absolutely no respect for work life balance. Genuinely do not care about you or your life. Poor comp vs peers at BB