Pros
great bunch of people who are smart and take responsibility for themselves and their work; great staff and client retention, so get to spend time building and doing things better, not filling holes/ re-teaching stuff; cool offices in great locations; people first attitude - focus on making sure people are doing things that interest them, rather than making a machine; interesting sectors of work; flat, informal structure means everyone can learn quickly from each other; people i know who've worked very hard have always been recognized and rewarded quickly and well; qual, quant and global offices work well together;
Cons
flat structure can mean some gaps in responsibilities/ wrong people on tasks sometimes; individual/ entrepreneurial attitude can mean different bits of the company moving in different directions without linking up as well as they could