Pros
Very prestigious, generally interesting work. Quinn has a fearsome reputation, so by working there, people consider you highly competent and accomplished. The associates I worked with were largely decent, if down-trodden people. A small number of partners were respected and well-liked.
Cons
Horribly abusive, toxic environment. Associates were miserable and quitting in droves. I have worked at two other Biglaw firms, so I have some frame of reference. In the brief time I was there, numerous associates quit. One guy walked out on December 23 with two hours' notice--it was that bad (Granted, his wife was a doctor, so he could pull a stunt like that. Most of us aren't so lucky). The partners were largely "screamers" and hypercritical without providing the least bit of training, mentoring, or assistance. It was a culture of blame and negativity. The support staff was far below average. There were no legal secretaries to speak of--instead, associates were expected to handle all of their own electronic filings and other duties that are often handled by secretaries in Biglaw. Almost immediately upon joining, it became apparent how Quinn manages to stay so profitable: it cuts corners everywhere and works associates to death.