William Blair reviews

Not the most sophisticated personnel, as expected since most guys at Blair go because they did not get an offer or last at a BB, arguably work more hours (sell-side M&A is very process-oriented in nature and most hours spent updating CRM, addressing and placing labels on hard copy CIMs to send to 300+ buyers), work is very administrative and not much technical skillset required and subsequently developed. Also, the smartest people don't necessarily do well at Blair, those are the ones that tend to leave for better things. You do well if you're a good fit, regardless of competence. They pride themselves on people staying for a long time, many analyst take associate promote and stay for years - I would argue it's because they have no other options.

long hours, somewhat stressful, intense at times